Merge branch...

Merge branch '154-nameerror-at-app-resint-live_documents-pdf-name-timedelta-is-not-defined' into 'master'

Resolve "NameError at /app/resint/live_documents/*.pdf: name 'timedelta' is not defined"

Closes #154

See merge request AlekSIS/official/AlekSIS-App-Chronos!212

aleksis/apps/chronos/util/chronos_helpers.py

+from datetime import timedelta
 from typing import TYPE_CHECKING, Optional
 
 from django.db.models import Count, Q