Add Ruby 3.2.5 variants for GitLab Rails CI images

What does this MR do and why?

Add Ruby 3.2.5 variants for GitLab Rails CI images, since it is the latest in the Ruby 3.2.x series

Checklist

• (If applicable) Add patches if required for upgrading Ruby version in https://gitlab.com/gitlab-org/gitlab-build-images/-/tree/master/patches/ruby.