We need a bug_id to comment and close Bugzillas when merging pull requests. UpdatePullRequest is already pulling the commit comment into buildbot code, we can leverage the same step to save bug_id as a property.
<rdar://problem/91263398>
Pull request: https://github.com/WebKit/WebKit/pull/244
Landed https://commits.webkit.org/249268@main (r292405)
Re-opening for pull request https://github.com/WebKit/WebKit/pull/259
Committed r292545 (249383@main): <https://commits.webkit.org/249383@main> Reviewed commits have been landed. Closing #259 and removing active labels.