Add the GitHubAppWebhookHandlerHook extension hook.
Review Request #15338 — Created Sept. 24, 2026 and updated — Latest diff uploaded
This adds an extension hook for registering GitHub App webhook handlers,
letting extensions act on GitHub events delivered to Review Board, like
pull requests being opened on a repository.
- Ran unit tests.
- Used in the Pull Request integration work.
- Built the docs and viewed.