[ruby/psych] Added condition for macOS homebrew

https://github.com/ruby/psych/commit/a876de5a82

Co-authored-by: David Rodríguez <deivid.rodriguez@riseup.net>

ext/psych/extconf.rb

@@ -7,7 +7,7 @@ require 'fileutils'
 
 dir_config 'libyaml'
 
-if enable_config("bundled-libyaml", false) || !(find_header('yaml.h') && find_library('yaml', 'yaml_get_version'))
+if enable_config("bundled-libyaml", false) || !pkg_config('yaml-0.1') && !(find_header('yaml.h') && find_library('yaml', 'yaml_get_version'))
   # Embed libyaml since we could not find it.
 
   $VPATH << "$(srcdir)/yaml"