Change the logging msg to remove unused var

subscribe_mail_lists.py

@@ -50,7 +50,7 @@ def mail_list_subscription(ch, method, properties, body):
         email_msg.set_content(listserv_cmd)
         if not args.dry_run:
             s.send_message(email_msg)
-        logging.info(f'This email will add user {username} to {key}\n{email_msg}')
+        logging.info(f'This email will add user {username} to listserv \n{email_msg}')
 
         s.quit()
         msg['task'] = task