compliance: Account for Zippy commits without PR in report summary (#54461)

The report summary previously assumed that every commit that had a
review would also have an associated PR - this was no longer the case
with Zippy PRs that are allowed without PR. This pull request fixes this
wrong assumption.

Release Notes:

- N/A
c8cda37d17Finn Evers committed on 4/22/2026, 12:01:56 AM· committed by GitHubparent6cdf954
1 file changedLine totals unavailable