Null out previous migration

Author: snigdhas

src/sentry/migrations/0641_backfill_group_attributes.py

@@ -7,7 +7,6 @@
 from typing import TYPE_CHECKING
 
 from django.conf import settings
-from django.db import migrations
 from django.db.backends.base.schema import BaseDatabaseSchemaEditor
 from django.db.migrations.state import StateApps
 from django.db.models import F, Window
@@ -178,10 +177,4 @@ class Migration(CheckedMigration):
         ("sentry", "0640_index_together"),
     ]
 
-    operations = [
-        migrations.RunPython(
-            backfill_group_attributes_to_snuba,
-            reverse_code=migrations.RunPython.noop,
-            hints={"tables": ["sentry_groupedmessage"]},
-        )
-    ]
+    operations = []