Modernize some Python constructs (#876)

* Update __future__ import, remove __metaclass__ assignment.

* Removing obsolete encoding comment.

* Remove unneccessary object inheritance.

plugins/modules/openssl_publickey_info.py

@@ -1,14 +1,9 @@
 #!/usr/bin/python
-# -*- coding: utf-8 -*-
-
 # Copyright (c) 2021, Felix Fontein <felix@fontein.de>
 # 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
 
 
 DOCUMENTATION = r"""
@@ -196,7 +191,7 @@ def main():
         except (IOError, OSError) as e:
             module.fail_json(
                 msg="Error while reading public key file from disk: {0}".format(e),
-                **result
+                **result,
             )
 
     backend, module_backend = select_backend(