* ext/psych/lib/psych.rb: [DOC] Fix a dead link in Psych by @rochefort [ci skip][fix GH-593]

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@45577 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

ext/psych/lib/psych.rb

@@ -21,7 +21,7 @@ require 'psych/class_loader'
 #
 # Psych is a YAML parser and emitter.
 # Psych leverages libyaml [Home page: http://pyyaml.org/wiki/LibYAML]
-# or [Git repo: https://github.com/zerotao/libyaml] for its YAML parsing
+# or [HG repo: https://bitbucket.org/xi/libyaml] for its YAML parsing
 # and emitting capabilities. In addition to wrapping libyaml, Psych also
 # knows how to serialize and de-serialize most Ruby objects to and from
 # the YAML format.