Improve Python code: address unused variables (#11049)

* Address F841 (unused variable).

* Reformat.

* Add changelog fragment.

* More cleanup.

* Remove trailing whitespace.

* Readd removed code as a comment with TODO.

plugins/modules/aerospike_migrations.py

@@ -167,7 +167,7 @@ try:
     import aerospike
     from time import sleep
     import re
-except ImportError as ie:
+except ImportError:
     LIB_FOUND = False
     LIB_FOUND_ERR = traceback.format_exc()
 else: