The author signed a CLA. "7 checks passed", and if you click "View Details" you see:
> license/cla All CLA requirements met.
Also mentioned in https://github.com/microsoft/calculator/blob/master/CONTRIBU...
> license/cla All CLA requirements met.
Also mentioned in https://github.com/microsoft/calculator/blob/master/CONTRIBU...
The page you linked indicates that a bot will comment on the PR. I am looking at https://github.com/microsoft/calculator/pull/553, but I do not see any bot-generated comments, other than the "All CLA requirements met." status line you mentioned; and I do not see a "cla-signed" or a "cla-not-required" tag on the PR.
Still annoying, regardless.
But it looks like the CONTRIBUTING.md file wasn't updated to reflect this change.