Pull request out-of-sync modal keeps appearing even after PR sync

[yk634]

What happened:
A modal saying "It appears that pull requests for this pipeline are out of sync" keeps appearing continuously.

Even after clicking the Sync button and successfully running the PR sync, when we click the Pull Request tab again, the same modal is shown repeatedly.

Based on our investigation, this seems to happen in the following situations:

1. For pipelines with sourceDirectory configured, pull request jobs unrelated to the pipeline can sometimes be created (for example, when the branch differs).

   • In such cases, PR jobs are created, but corresponding pipeline events are not.
   • As a result, the system appears to judge that there are pull requests that require syncing, which causes the modal to be shown.

2. In our environment, we periodically delete old events, builds, and archived job data from the database to reduce data volume.

   • When there are old pull requests that remain open, only the event data may be deleted while the PR job records remain.
   • This also causes the system to determine that there are PRs requiring sync, and the modal keeps appearing.

What you expected to happen:

At minimum, once Sync PR has been executed successfully, the modal should be dismissed and not shown again unless there is a new actual mismatch that requires syncing.

How to reproduce it:

1. Create a pipeline with sourceDirectory configured.
2. Create or update a pull request (e.g. on a different branch or unrelated to the pipeline), and trigger PR Sync by any means.
3. Open the pipeline page and click the Pull Request tab.
4. Observe that the modal "It appears that pull requests for this pipeline are out of sync" is displayed.
5. Click Sync to run PR sync.
6. Click the Pull Request tab again.
7. Observe that the same modal is displayed again, even though PR sync was already executed.

[minghay]

@yk634 I'm thinking that it may be best to remove the PR sync modal completely from the v2 UI. It was a good idea at the time, but there are too many pitfalls that it's not worth keeping the modal around.