Remove manager on supervision substitution

aleksis/apps/chronos/migrations/0001_initial.py

@@ -305,7 +305,8 @@ class Migration(migrations.Migration):
                 "verbose_name_plural": "Supervision substitutions",
                 "ordering": ["date", "supervision"],
             },
-            managers=[("objects", django.contrib.sites.managers.CurrentSiteManager()),],
+            managers=[
+            ],
         ),
         migrations.CreateModel(
             name="SupervisionArea",