Ruby

fix mortal_dynamic_symbol count

• test/objspace/test_objspace.rb (test_count_symbols): exclude a
  dynamic symbol which has been turned into immortal by
  define_method.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@59146 b2dd03c8-39d4-4d8f-98ff-823fe69b080e