Add Ruby feature consistency tests

[lloeki]

Some bundled gems (or default gems in older versions) are dependent on the OS providing native libraries:

• openssl
• gdbm (unbundled on 3.3+)
• fiddle
• psych
• zlib

Some versions have conditional support for certain features:

• yjit (available since 3.1, requires a Rust compiler since 3.2)

These conditionals fail silently if their dependencies are unsatisfied: this may result in a successful build of Ruby that end up lacking expected features.

Therefore we can only ensure our builds are consistent in features via testing after the fact.

Example smoke tests:

ruby -rzlib -e 'p Zlib.zlib_version'
ruby -ropenssl -e 'p OpenSSL::Cipher.ciphers'
ruby -rjson -e 'puts JSON.dump({foo: "bar"})'
ruby -ryaml -e 'puts YAML.dump({foo: "bar"})'
ruby -rfiddle -e 'Fiddle.dlopen(nil).tap { |libc| p Fiddle::Function.new(libc["malloc"], [Fiddle::TYPE_SIZE_T], Fiddle::TYPE_VOIDP).call(42) }'

ruby --yjit -e ''