Support Ruby 4.0 (#25051)

Note: Building the protobuf gem with versions of rubygems that include https://github.com/ruby/rubygems/pull/8569 is broken due to the issue reported in https://github.com/ruby/rubygems/issues/9244. Workaround is to use a rubygems version below 3.7.0 to build the gem.

Closes #25051

COPYBARA_INTEGRATE_REVIEW=https://github.com/protocolbuffers/protobuf/pull/25051 from frederikspang:main 83f91c76e18e84083439ba6af3c9508fbce1e453
PiperOrigin-RevId: 858713403