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/callback/logentries.py

@@ -254,7 +254,7 @@ class CallbackModule(CallbackBase):
 
         try:
             self.token = self.get_option("token")
-        except KeyError as e:
+        except KeyError:
             self._display.warning(
                 "Logentries token was not provided, this is required for this callback to operate, disabling"
             )