Redmine

Support for Ruby 3.2 ended on 1 Apr 2026:
https://www.ruby-lang.org/ja/downloads/branches/

This patch drops support for Ruby 3.2.

Additionally, css_parser 3.0.0, which resolves the bundle-audit warning in GitHub Actions, requires Ruby 3.3 or later:
https://github.com/redmine/redmine/actions/runs/32332116912/job/96314625030

I have confirmed that linting and all tests pass.