Redmine

Following https://www.redmine.org/projects/redmine/wiki/RedmineInstall

Stuck on Step 5
This step generates a random key used by Rails to encode cookies storing session data thus preventing their tampering.
Generating a new secret token invalidates all existing sessions after restart.

bundle exec rake generate_secret_token

result in (see rake aborted message)

/usr/lib/ruby/vendor_ruby/rubygems/defaults/operating_system.rb:10: warning: constant Gem::ConfigMap is deprecated
/usr/lib/ruby/vendor_ruby/rubygems/defaults/operating_system.rb:10: warning: constant Gem::ConfigMap is deprecated
/usr/lib/ruby/vendor_ruby/rubygems/defaults/operating_system.rb:29: warning: constant Gem::ConfigMap is deprecated
/usr/lib/ruby/vendor_ruby/rubygems/defaults/operating_system.rb:30: warning: constant Gem::ConfigMap is deprecated
/usr/lib/ruby/vendor_ruby/rubygems/defaults/operating_system.rb:10: warning: constant Gem::ConfigMap is deprecated
/usr/lib/ruby/vendor_ruby/rubygems/defaults/operating_system.rb:10: warning: constant Gem::ConfigMap is deprecated
/usr/lib/ruby/vendor_ruby/rubygems/defaults/operating_system.rb:10: warning: constant Gem::ConfigMap is deprecated
/usr/lib/ruby/vendor_ruby/rubygems/defaults/operating_system.rb:29: warning: constant Gem::ConfigMap is deprecated
/usr/lib/ruby/vendor_ruby/rubygems/defaults/operating_system.rb:30: warning: constant Gem::ConfigMap is deprecated
/usr/lib/ruby/vendor_ruby/rubygems/defaults/operating_system.rb:29: warning: constant Gem::ConfigMap is deprecated
/usr/lib/ruby/vendor_ruby/rubygems/defaults/operating_system.rb:30: warning: constant Gem::ConfigMap is deprecated
/usr/lib/ruby/vendor_ruby/rubygems/defaults/operating_system.rb:10: warning: constant Gem::ConfigMap is deprecated
/usr/lib/ruby/vendor_ruby/rubygems/defaults/operating_system.rb:10: warning: constant Gem::ConfigMap is deprecated
/usr/lib/ruby/vendor_ruby/rubygems/defaults/operating_system.rb:10: warning: constant Gem::ConfigMap is deprecated
/var/lib/gems/2.5.0/gems/psych-4.0.6/lib/psych/versions.rb:5: warning: already initialized constant Psych::VERSION
/usr/lib/ruby/2.5.0/psych/versions.rb:4: warning: previous definition of VERSION was here
/var/lib/gems/2.5.0/gems/psych-4.0.6/lib/psych/class_loader.rb:7: warning: already initialized constant Psych::ClassLoader::BIG_DECIMAL
/usr/lib/ruby/2.5.0/psych/class_loader.rb:7: warning: previous definition of BIG_DECIMAL was here
/var/lib/gems/2.5.0/gems/psych-4.0.6/lib/psych/class_loader.rb:8: warning: already initialized constant Psych::ClassLoader::COMPLEX
/usr/lib/ruby/2.5.0/psych/class_loader.rb:8: warning: previous definition of COMPLEX was here
/var/lib/gems/2.5.0/gems/psych-4.0.6/lib/psych/class_loader.rb:9: warning: already initialized constant Psych::ClassLoader::DATE
/usr/lib/ruby/2.5.0/psych/class_loader.rb:9: warning: previous definition of DATE was here
/var/lib/gems/2.5.0/gems/psych-4.0.6/lib/psych/class_loader.rb:10: warning: already initialized constant Psych::ClassLoader::DATE_TIME
/usr/lib/ruby/2.5.0/psych/class_loader.rb:10: warning: previous definition of DATE_TIME was here
/var/lib/gems/2.5.0/gems/psych-4.0.6/lib/psych/class_loader.rb:11: warning: already initialized constant Psych::ClassLoader::EXCEPTION
/usr/lib/ruby/2.5.0/psych/class_loader.rb:11: warning: previous definition of EXCEPTION was here
/var/lib/gems/2.5.0/gems/psych-4.0.6/lib/psych/class_loader.rb:12: warning: already initialized constant Psych::ClassLoader::OBJECT
/usr/lib/ruby/2.5.0/psych/class_loader.rb:12: warning: previous definition of OBJECT was here
/var/lib/gems/2.5.0/gems/psych-4.0.6/lib/psych/class_loader.rb:13: warning: already initialized constant Psych::ClassLoader::PSYCH_OMAP
/usr/lib/ruby/2.5.0/psych/class_loader.rb:13: warning: previous definition of PSYCH_OMAP was here
/var/lib/gems/2.5.0/gems/psych-4.0.6/lib/psych/class_loader.rb:14: warning: already initialized constant Psych::ClassLoader::PSYCH_SET
/usr/lib/ruby/2.5.0/psych/class_loader.rb:14: warning: previous definition of PSYCH_SET was here
/var/lib/gems/2.5.0/gems/psych-4.0.6/lib/psych/class_loader.rb:15: warning: already initialized constant Psych::ClassLoader::RANGE
/usr/lib/ruby/2.5.0/psych/class_loader.rb:15: warning: previous definition of RANGE was here
/var/lib/gems/2.5.0/gems/psych-4.0.6/lib/psych/class_loader.rb:16: warning: already initialized constant Psych::ClassLoader::RATIONAL
/usr/lib/ruby/2.5.0/psych/class_loader.rb:16: warning: previous definition of RATIONAL was here
/var/lib/gems/2.5.0/gems/psych-4.0.6/lib/psych/class_loader.rb:17: warning: already initialized constant Psych::ClassLoader::REGEXP
/usr/lib/ruby/2.5.0/psych/class_loader.rb:17: warning: previous definition of REGEXP was here
/var/lib/gems/2.5.0/gems/psych-4.0.6/lib/psych/class_loader.rb:18: warning: already initialized constant Psych::ClassLoader::STRUCT
/usr/lib/ruby/2.5.0/psych/class_loader.rb:18: warning: previous definition of STRUCT was here
/var/lib/gems/2.5.0/gems/psych-4.0.6/lib/psych/class_loader.rb:19: warning: already initialized constant Psych::ClassLoader::SYMBOL
/usr/lib/ruby/2.5.0/psych/class_loader.rb:19: warning: previous definition of SYMBOL was here
rake aborted!
SyntaxError: (eval):2: syntax error, unexpected =>, expecting '}'
  load {"Complex"=>Complex, "Exception"=>Excepti...
                 ^~
(eval):2: dynamic constant assignment
  load {"Complex"=>Complex, "Exception"=>Exception, "Obj...
                          ^
(eval):2: syntax error, unexpected =>, expecting &. or :: or '[' or '.'
...omplex"=>Complex, "Exception"=>Exception, "Object"=>Object, ...
...                             ^~
(eval):2: dynamic constant assignment
...omplex, "Exception"=>Exception, "Object"=>Object, "Psych::Om...
...                              ^
(eval):2: syntax error, unexpected =>, expecting &. or :: or '[' or '.'
...ception"=>Exception, "Object"=>Object, "Psych::Omap"=>Psych:...
...                             ^~
(eval):2: dynamic constant assignment
..."=>Exception, "Object"=>Object, "Psych::Omap"=>Psych::Omap, ...
...                              ^
(eval):2: syntax error, unexpected =>, expecting &. or :: or '[' or '.'
...bject"=>Object, "Psych::Omap"=>Psych::Omap, "Psych::Set"=>Ps...
...                             ^~
(eval):2: dynamic constant assignment
...ct, "Psych::Omap"=>Psych::Omap, "Psych::Set"=>Psych::Set, "R...
...                              ^
(eval):2: syntax error, unexpected =>, expecting &. or :: or '[' or '.'
...p"=>Psych::Omap, "Psych::Set"=>Psych::Set, "Range"=>Range, "...
...                             ^~
(eval):2: dynamic constant assignment
...Omap, "Psych::Set"=>Psych::Set, "Range"=>Range, "Rational"=>...
...                              ^
(eval):2: syntax error, unexpected =>, expecting &. or :: or '[' or '.'
...ch::Set"=>Psych::Set, "Range"=>Range, "Rational"=>Rational, ...
...                             ^~
(eval):2: dynamic constant assignment
...t"=>Psych::Set, "Range"=>Range, "Rational"=>Rational, "Struc...
...                              ^
(eval):2: syntax error, unexpected =>, expecting &. or :: or '[' or '.'
...t, "Range"=>Range, "Rational"=>Rational, "Struct"=>Struct, "...
...                             ^~
(eval):2: dynamic constant assignment
..."=>Range, "Rational"=>Rational, "Struct"=>Struct, "Symbol"=>...
...                              ^
(eval):2: syntax error, unexpected =>, expecting &. or :: or '[' or '.'
...Rational"=>Rational, "Struct"=>Struct, "Symbol"=>Symbol, "Re...
...                             ^~
(eval):2: dynamic constant assignment
...l"=>Rational, "Struct"=>Struct, "Symbol"=>Symbol, "Regexp"=>...
...                              ^
(eval):2: syntax error, unexpected =>, expecting &. or :: or '[' or '.'
...l, "Struct"=>Struct, "Symbol"=>Symbol, "Regexp"=>Regexp}
...                             ^~
(eval):2: dynamic constant assignment
...uct"=>Struct, "Symbol"=>Symbol, "Regexp"=>Regexp}
...                              ^
(eval):2: syntax error, unexpected =>, expecting &. or :: or '[' or '.'
...t, "Symbol"=>Symbol, "Regexp"=>Regexp}
...                             ^~
/var/lib/gems/2.5.0/gems/psych-4.0.6/lib/psych/class_loader.rb:38:in `class_eval'
/var/lib/gems/2.5.0/gems/psych-4.0.6/lib/psych/class_loader.rb:38:in `block in <class:ClassLoader>'
/var/lib/gems/2.5.0/gems/psych-4.0.6/lib/psych/class_loader.rb:36:in `each'
/var/lib/gems/2.5.0/gems/psych-4.0.6/lib/psych/class_loader.rb:36:in `<class:ClassLoader>'
/var/lib/gems/2.5.0/gems/psych-4.0.6/lib/psych/class_loader.rb:6:in `<module:Psych>'
/var/lib/gems/2.5.0/gems/psych-4.0.6/lib/psych/class_loader.rb:5:in `<top (required)>'
/var/lib/gems/2.5.0/gems/psych-4.0.6/lib/psych/nodes/node.rb:3:in `require_relative'
/var/lib/gems/2.5.0/gems/psych-4.0.6/lib/psych/nodes/node.rb:3:in `<top (required)>'
/var/lib/gems/2.5.0/gems/psych-4.0.6/lib/psych/nodes.rb:2:in `require_relative'
/var/lib/gems/2.5.0/gems/psych-4.0.6/lib/psych/nodes.rb:2:in `<top (required)>'
/var/lib/gems/2.5.0/gems/psych-4.0.6/lib/psych.rb:15:in `require_relative'
/var/lib/gems/2.5.0/gems/psych-4.0.6/lib/psych.rb:15:in `<top (required)>'
/var/lib/gems/2.5.0/gems/bundler-2.3.24/lib/bundler/runtime.rb:60:in `require'
/var/lib/gems/2.5.0/gems/bundler-2.3.24/lib/bundler/runtime.rb:60:in `block (2 levels) in require'
/var/lib/gems/2.5.0/gems/bundler-2.3.24/lib/bundler/runtime.rb:55:in `each'
/var/lib/gems/2.5.0/gems/bundler-2.3.24/lib/bundler/runtime.rb:55:in `block in require'
/var/lib/gems/2.5.0/gems/bundler-2.3.24/lib/bundler/runtime.rb:44:in `each'
/var/lib/gems/2.5.0/gems/bundler-2.3.24/lib/bundler/runtime.rb:44:in `require'
/var/lib/gems/2.5.0/gems/bundler-2.3.24/lib/bundler.rb:186:in `require'
/opt/redmine/config/application.rb:18:in `<top (required)>'
/opt/redmine/Rakefile:5:in `require'
/opt/redmine/Rakefile:5:in `<top (required)>'
/var/lib/gems/2.5.0/gems/rake-13.0.6/exe/rake:27:in `<top (required)>'
(See full trace by running task with --trace)

How can this be resolved?

ruby -v
ruby 2.5.1p57 (2018-03-29 revision 63029) [x86_64-linux-gnu]

rails --version
Rails 6.1.7

lsb_release -a
Distributor ID: Ubuntu
Description:    Ubuntu 18.04.6 LTS
Release:        18.04
Codename:       bionic

database Postgres