Fix cache-hit in flakiness detection performance test (#8482)
We don't want build cache hit in performance flakiness detection, however, previously the coordinator build resolves "flakiness-detection-commit" baseline to real commit id "5.3-commit-237a600", resulting in unexpected cache hit.
This PR fixes it by:
- On coordinator's side, pass "flakiness-detection-commit" as it is to worker build.
- On worker's side, worker build resolves "flakiness-detection-commit" to real commit version - this disables build cache.
Since `DetermineBaselines` is becoming more and more complex, this PR also adds a unit test for `DetermineBaselines` class.
16 Feb 19 e4d21b8adf8c9482aeebd26bdda5cf05de809448
Fetch branch name from environment variable when necessary (#7947)
Previously we use JGit's branch, which might be not accurate.
Now we prefer environment variable over JGit.
10 Dec 18 4dab8a22fcc9408cb7641b39ed903876e4bf7964