docker modules: various adjustments (#51700)

* Move docker_ module_utils into subpackage.

* Remove docker_ prefix from module_utils.docker modules.

* Adding jurisdiction for module_utils/docker to $team_docker.

* Making docker* unit tests community supported.

* Linting.

* Python < 2.6 is not supported.

* Refactoring docker-py version comments. Moving them to doc fragments. Cleaning up some indentations.

test/units/module_utils/docker/test_common.py

@@ -1,6 +1,6 @@
 import pytest
 
-from ansible.module_utils.docker_common import (
+from ansible.module_utils.docker.common import (
     compare_dict_allow_more_present,
     compare_generic,
 )