Ruby

test_thread.rb: descriptive assertions

• test/ruby/test_thread.rb: (test_local_barrier),
  (test_status_and_stop_p, test_recursive_outer, test_stack_size): use
  more descriptive assertions.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@38520 b2dd03c8-39d4-4d8f-98ff-823fe69b080e