Small CLI cleanups

* yapf changes
* Fix the cformat test
* Make the normpath test work when run from /
* `qmk config`: Mark `--read-only` as arg_only

lib/python/qmk/tests/attrdict.py

@@ -3,7 +3,6 @@ class AttrDict(dict):
 
     This should only be used to mock objects for unit testing. Please do not use this outside of qmk.tests.
     """
-
     def __init__(self, *args, **kwargs):
         super(AttrDict, self).__init__(*args, **kwargs)
         self.__dict__ = self