feat!: switch from rv-ruby to jdx/ruby

[p0deje]

This PR changes current portable Ruby installation from rv-ruby to jdx/ruby.

The main reason to make the change is that latter ships with common headers/libraries needed to install gems with native extensions. When using rv-ruby, we had to exclude some gems from installation and instead use default gem versions that ship with Ruby, making it impossible to use certain gem + version combinations. A common example is a psych gem that needs libyaml to compile its native extensions. jdx/ruby has libyaml headers and static library that can be used for compilation, though we still need to tell Bundler how to find it. Since there is no more need for excluding gems during bundle install, the related logic was completely removed.

To make overall transition better, users now only need to add portable_ruby = True attribute which will silently be ignored for Ruby versions and platforms not currently supported (JRuby, TruffleRuby, Windows). This is important for projects like Selenium that test across a matrix of interpreter/OS combinations. Eventually, if everything works well, we can flip the portable_ruby to be True by default.

PR also adds default checksums for portable Rubies, so users don't have to run anything to ensure Ruby is properly store in the repository cache. The only case where it might be needed is if a new version of Ruby came out published to jdx/ruby. Users can still run bazel run @rules_ruby//tools/generate_portable_ruby_checksums to fetch the checksums until rules_ruby is updated.

Portable Rubies unblock RBE support on MRI, though the current toolchain still needs to be reworked to handle platform constraints and properly provide headers/libraries path to bundle install action.