Add Ruby 3.1 to build

What does this MR do and why?

Ruby 3.2 contains a number of kwargs fixes, and Rails 7 may be a prerequisite for Ruby 3.2. We'll want to test and deploy Ruby 3.1 before jumping to 3.2.

Ruby 3.1 requires at least rubygems v3.1.3. Let's just bump everything to 3.4, and consolidate the Ruby 3.2 build.

Related epic: &10034 (closed)

Checklist

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