Focus & Skip broken for unittest.TestCase decorated by @patch

For unittest.TestCase classes that are decorated with https://docs.python.org/3/library/unittest.mock.html#patch, when we do ftest or xtest, the decorator does to patch these methods, and we get a TypeError when running the test.

This happens because @patch is evaluated on the class loading, and it patches all methods there that begin with "test". Since ftest and xtest don't match the search, they're not decorated, and become broken.