Remove bans cache versioning from old cache versioning feature

misago/users/migrations/0003_bans_version_tracker.py

@@ -1,11 +1,6 @@
 from django.db import migrations
 
 
-def register_bans_version_tracker(apps, schema_editor):
-    from misago.core.migrationutils import cachebuster_register_cache
-    cachebuster_register_cache(apps, "misago_bans")
-
-
 class Migration(migrations.Migration):
     """Migration superseded by 0016"""
 
@@ -14,7 +9,4 @@ class Migration(migrations.Migration):
         ('misago_core', '0001_initial'),
     ]
 
-    operations = [
-        # FIXME: remove this operation
-        migrations.RunPython(register_bans_version_tracker),
-    ]
+    operations = []