chore: add ast-grep rule to convert Optional[T] to T | None (#25560)

Co-authored-by: autofix-ci[bot] <114827586+autofix-ci[bot]@users.noreply.github.com>

api/services/billing_service.py

@@ -1,5 +1,5 @@
 import os
-from typing import Literal, Optional
+from typing import Literal
 
 import httpx
 from tenacity import retry, retry_if_exception_type, stop_before_delay, wait_fixed
@@ -73,7 +73,7 @@ class BillingService:
     def is_tenant_owner_or_admin(current_user: Account):
         tenant_id = current_user.current_tenant_id
 
-        join: Optional[TenantAccountJoin] = (
+        join: TenantAccountJoin | None = (
             db.session.query(TenantAccountJoin)
             .where(TenantAccountJoin.tenant_id == tenant_id, TenantAccountJoin.account_id == current_user.id)
             .first()