Windows, because this tests a platform specific feature and it'll never be
supported on ruby on Windows.
* test/ruby/test_dir_m17n.rb (TestDir_M17N#test_filename_extutf8_invalid,
TestDir_M17N#test_filename_as_bytes_extutf8): ditto.
* test/open-uri/test_open-uri.rb
(TestOpenURI#test_find_proxy_case_sensitive_env): ditto.
* test/dl/test_handle.rb (DL::TestHandle#test_NEXT,
DL::TestHandle#test_DEFAULT): ditto.
git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@31174 b2dd03c8-39d4-4d8f-98ff-823fe69b080e