Python code modernization, 3/n (#1157)

* Remove __metaclass__ = type.

for i in $(grep -REl '__metaclass__ = type' plugins/ tests/); do
  sed -e '/^__metaclass__ = type/d' -i $i;
done

* Remove super arguments, and stop inheriting from object.

plugins/module_utils/_api/tls.py

@@ -18,7 +18,7 @@ from . import errors
 from .transport.ssladapter import SSLHTTPAdapter
 
 
-class TLSConfig(object):
+class TLSConfig:
     """
     TLS configuration.