avoid breaking upgrades from certain AWX versions

the prior version of this migration was rewritten, so we should
run the function again to really make sure that cleanup happens

awx/main/migrations/0122_really_remove_cloudforms_inventory.py

@@ -0,0 +1,13 @@
+from django.db import migrations
+from awx.main.migrations._inventory_source import delete_cloudforms_inv_source
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('main', '0121_delete_toweranalyticsstate'),
+    ]
+
+    operations = [
+        migrations.RunPython(delete_cloudforms_inv_source),
+    ]