Way of identifying tests on the dashboard that have been fixed

Currently, the [short test report dashboard](https://dask.github.io/distributed/test_short_report.html) shows 5 recently failing tests on main.

But 3 of those should already be fixed, and as you can see, they're all green in more recent runs:
- https://github.com/dask/distributed/pull/6954
- https://github.com/dask/distributed/pull/6955

It would be nice if there was a way for a PR to instruct the test dashboard that a test is expected to be fixed, and hide it immediately (as long as it's all green subsequent to that PR). Then, the dashboard would more accurately reflect the latest status of what tests are flaky. Or, if an expected-fixed test failed, it could highlight prominently that the fix didn't work.

Current dashboard, for reference:


cc @hendrikmakait @ian-r-rose @fjetter