Remove unused imports

aleksis/apps/lesrooster/models.py

-from copy import deepcopy
 from datetime import date, datetime
 from typing import Optional, Union
 

aleksis/apps/lesrooster/util/signal_handlers.py

 import logging
 
-from django.db.models import Q
-
 
 def post_save_handler(sender, instance, created, **kwargs):
     """Sync the instance with Chronos after it has been saved."""