Ruby

Fix Rinda test teardown for omitted tests

New test failures on MINGW appeared after
c2e37c8ff7da395f33fae546d9ae9e2408fc9236.

  1) Error:
Rinda::TupleSpaceProxyTest#test_00_template:
NoMethodError: undefined method `stop_service' for nil:NilClass
    D:/a/ruby/ruby/src/test/rinda/test_rinda.rb:516:in `teardown'

  2) Error:
Rinda::TupleSpaceProxyTest#test_ruby_talk_264062:
NoMethodError: undefined method `stop_service' for nil:NilClass
    D:/a/ruby/ruby/src/test/rinda/test_rinda.rb:516:in `teardown'

Teardown happens even when the test is omitted.

See: https://github.com/ruby/ruby/runs/7058984522