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/_module_container/module.py

@@ -26,7 +26,7 @@ from ansible_collections.community.docker.plugins.module_utils._util import (
 
 class Container(DockerBaseClass):
     def __init__(self, container, engine_driver):
-        super(Container, self).__init__()
+        super().__init__()
         self.raw = container
         self.id = None
         self.image = None