Fix send_bundled_notification task (#4696)

# What this PR does
Fix scheduling `perform_notification` from `send_bundled_notification`
task - leftover after resolving merge conflict

## Checklist

- [ ] Unit, integration, and e2e (if applicable) tests updated
- [x] Documentation added (or `pr:no public docs` PR label added if not
required)
- [x] Added the relevant release notes label (see labels prefixed w/
`release:`). These labels dictate how your PR will
    show up in the autogenerated release notes.

engine/apps/alerts/tasks/notify_user.py

@@ -626,6 +626,7 @@ def send_bundled_notification(user_notification_bundle_id: int):
                     schedule_perform_notification_task,
                     log_record_notification_triggered.pk,
                     log_record_notification_triggered.alert_group_id,
+                    False,
                 )
             )
             notifications.delete()