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/dpkg_divert.py

@@ -332,7 +332,7 @@ def main():
                 if os.path.exists(b_old) and not os.path.exists(b_new):
                     try:
                         os.rename(b_old, b_new)
-                    except OSError as e:
+                    except OSError:
                         pass
 
     if not module.check_mode: