Improve handling of 429 responses

[mozfreddyb]

The issue is with "Assigned without recent activity" (under Stalled & Longstanding) for my security components.

DevTools logging says

Cross-Origin Request Blocked: The Same Origin Policy disallows reading the remote resource at https://bugzilla.mozilla.org/rest/bug/1714247/comment?new_since=2024-10-31. (Reason: CORS request did not succeed). Status code: (null).

However loading the URL https://bugzilla.mozilla.org/rest/bug/1714247/comment?new_since=2024-10-31 does get me a access-allow-origin response header.

I am not entirely sure who's at fault though.

[globau]

You're hitting BMO's rate limit, and BugDash isn't handling that gracefully (in part because BMO's error response is missing the CORS headers).

[globau]

I believe that due to the missing CORS headers it isn't possible to take appropriate action based on the response code.

Filed and blocked by https://bugzilla.mozilla.org/show_bug.cgi?id=1933982