Since SERVER-136977, CheckPerfResultTestCase.run_test catches every exception other than ServerFailure and TestFailure, logs it, and lets the test pass. When a metric fails its threshold check on a PR or merge queue run, _check_thresholds looks up override comments through the GitHub API: get_pull, get_issue_comments, get_review_comments, and get_comments. An error from any of these calls is swallowed by run_test, so a confirmed regression with no authorized override is reported as passing.

Before SERVER-136977, the dynamic test runner recorded the failure before the outer handler swallowed the exception.

Acceptance criteria

• An error during the override lookup after a failed metric fails the test with the threshold check ServerFailure.
• Errors in report generation and baseline lookup stay non-blocking.
• A unit test drives this case through run_test.

The fix also needs to go into the v9.0 backport of SERVER-136977, BACKPORT-30246.