For the CleanUpCache workflow run triggered by PR workflows, there is a simple way of getting the PR number. The full event webhook payload is available as a json file and it contains the number of the triggering PR. So we don't need to upload the PR number as an artifact.
For the post-PR cleanup, we could also clean up the cache directly without uploading the PR number and triggering a workflow run for cleaning.
For the CleanUpCache workflow run triggered by PR workflows, there is a simple way of getting the PR number. The full event webhook payload is available as a json file and it contains the number of the triggering PR. So we don't need to upload the PR number as an artifact.
For the post-PR cleanup, we could also clean up the cache directly without uploading the PR number and triggering a workflow run for cleaning.