<!-- Describe your changes in detail -->
Two drop null constraint queries were missing in v2_compatible_migrations directory. Added those.
1. Dropping not null on confirm column in payment_attempt.
2. Dropping not null on internal_reference_id in refunds.
To implement this **search_filter** feature, you'll need to modify these architectural layers:


**1. Other**
   - `.github/CODEOWNERS`
   - `v2_compatible_migrations/2024-08-28-081757_drop_not_null_constraints_on_v1_columns/down.sql`
   - `v2_compatible_migrations/2024-08-28-081757_drop_not_null_constraints_on_v1_columns/up.sql`
{"pr_number": 8940, "pr_title": "chore: include missing drop null constraint queries in v2_compatible_migrations", "merged_at": "2025-08-21T14:12:41Z", "intent": {"feature_type": "search_filter", "action": "add_feature", "entities": ["payment", "user", "refund"]}, "hierarchy": {"other": [".github/CODEOWNERS", "v2_compatible_migrations/2024-08-28-081757_drop_not_null_constraints_on_v1_columns/down.sql", "v2_compatible_migrations/2024-08-28-081757_drop_not_null_constraints_on_v1_columns/up.sql"]}, "change_types": {}, "has_identifier_data": false, "commits_matched": 0, "match_method": "none"}