Use in dict rather than "in dict.keys()". Fix linting warnings about "not in". (#8298)

* Fixed a few linting warnings for if not x in y.

These should have been caught by pylint, but weren't.

* Replaced "x in y.keys()" with "x in y".

It's much faster, and more Pythonic.

certbot-apache/certbot_apache/_internal/parser.py

@@ -799,7 +799,7 @@ class ApacheParser(object):
     def _parsed_by_parser_paths(self, filep, paths):
         """Helper function that searches through provided paths and returns
         True if file path is found in the set"""
-        for directory in paths.keys():
+        for directory in paths:
             for filename in paths[directory]:
                 if fnmatch.fnmatch(filep, os.path.join(directory, filename)):
                     return True