[stable-5] Remove unneccessary imports (#5977)

* Remove unneccessary imports (#5940)

* Remove unneccessary imports.

* Keep unnecessary imports in module_utils - for now.

* Make older sanity tests shut up.

* Also make flake8 happier.

(cherry picked from commit 2b8ac3c629)

* Re-add os import.

plugins/module_utils/oracle/oci_utils.py

@@ -10,13 +10,14 @@ import logging
 import logging.config
 import os
 import tempfile
-from datetime import datetime
+# (TODO: remove next line!)
+from datetime import datetime  # noqa: F401, pylint: disable=unused-import
 from operator import eq
 
 import time
 
 try:
-    import yaml
+    import yaml  # noqa: F401, pylint: disable=unused-import
 
     import oci
     from oci.constants import HEADER_NEXT_PAGE