alias value take if Ractor#value is not defined

[ko1]

Ractor#value was newly introduced but it can be emulated with Ractor#take if Ractor.yield is not used.

https://bugs.ruby-lang.org/issues/21262

[eregon]

This feels wrong because I would never expect a test harness to define extra methods on core classes (except maybe assertions methods).
For instance it might lead people to believe Ractor#value is always available, and a gem might even rely on that, but the method doesn't exist on Ruby 3.4 and would break when someone actually uses it outside the test harness.
I think Ractor#take should be re-added in ruby/ruby (could be deprecated).