tests: add callback to clear timezone cache on settings update (#89097)

tests/conftest.py

@@ -1,5 +1,9 @@
 import django_webtest
 import pytest
+from django.core.signals import setting_changed
+from django.dispatch import receiver
+
+from chrono.utils.timezone import get_default_timezone
 
 
 @pytest.fixture
@@ -23,3 +27,10 @@ def nocache(settings):
             'BACKEND': 'django.core.cache.backends.dummy.DummyCache',
         }
     }
+
+
+@receiver(setting_changed)
+def update_connections_time_zone(**kwargs):
+    if kwargs['setting'] == 'TIME_ZONE':
+        # Reset local time zone lru cache
+        get_default_timezone.cache_clear()