[ruby/psych] Fix the test that does not work with libyaml-0.1.7
https://github.com/ruby/psych/commit/542cf9754f
[ruby/psych] Fix the test that does not work with libyaml-0.1.7
https://github.com/ruby/psych/commit/542cf9754f