The workflow checked out pull_request.base.sha, the base recorded when the
pull request was opened, and ran that revision's check_conventions.py. A rule
merged after a pull request was opened never ran on it: #7005 added
APS5_NO_WGI without an ENVIRONMENT.md row and passed with the checker of
07e741481, which had no env-reference rule.
Check out the current tip of the base branch and pass it as --base; the
checker already diffs from the merge base, so only the pull request's own
changes are checked. A name documented on the base branch after the branch
point now counts as documented unless the pull request removes its row.
Co-Authored-By: Claude Opus 5.5 <[email protected]>
