Prepare 5.0.0 (#1123)

* Bump version to 5.0.0-a1.

* Drop support for ansible-core 2.15 and 2.16.

* Remove Python 2 and early Python 3 compatibility.

plugins/plugin_utils/common_api.py

@@ -2,8 +2,7 @@
 # GNU General Public License v3.0+ (see LICENSES/GPL-3.0-or-later.txt or https://www.gnu.org/licenses/gpl-3.0.txt)
 # SPDX-License-Identifier: GPL-3.0-or-later
 
-from __future__ import (absolute_import, division, print_function)
-__metaclass__ = type
+from __future__ import annotations
 
 
 from ansible.errors import AnsibleConnectionFailure

plugins/plugin_utils/socket_handler.py

@@ -6,7 +6,7 @@ from __future__ import (absolute_import, division, print_function)
 __metaclass__ = type
 
 
-from ansible_collections.community.docker.plugins.module_utils.selectors import selectors
+import selectors
 
 from ansible_collections.community.docker.plugins.module_utils.socket_handler import (
     DockerSocketHandlerBase,

plugins/plugin_utils/unsafe.py

@@ -2,8 +2,7 @@
 # GNU General Public License v3.0+ (see LICENSES/GPL-3.0-or-later.txt or https://www.gnu.org/licenses/gpl-3.0.txt)
 # SPDX-License-Identifier: GPL-3.0-or-later
 
-from __future__ import (absolute_import, division, print_function)
-__metaclass__ = type
+from __future__ import annotations
 
 import re