This is a GitHub post-receive hook that will automatically close review requests as "submitted" after a push. To determine which review requests should be closed, it scans through each commit's commit message for the following strings (case-insensitive): "Reviewed at <reviewboard_url>/r/<id>" or "Review request #<id>". The regex used for this can be overriden in settings_local.py.

Added the post-receive webhook URL to a private GitHub repository, and tested different pushes:

- Commit with a review request ID that is not submitted (verified that the review request is closed and set to submitted)

- Commit with a review request ID that is already submitted (got a warning that the review request is already submitted)

- Commit without a review request ID in the commit message (got a debug message that no matching review request ID was found)

- Commit with a private review request (verified that the review request is closed)

- Commits referencing the same review request ID

- Multiple commits

- Merge commits

- Branch creation and deletion

- Commits pushed to two branches
I also overrode the regex and flags in settings_local.py, and got the expected change in matching review request IDs.