[CT] Experiment by increasing to 20 parallel goroutines in metrics analysis
[CT] Experiment by increasing to 20 parallel goroutines in metrics analysis

Bug: skia:7872
Change-Id: Idae26a062e9d43a02ebfa6a2d7585613ecdb9523
Reviewed-on: https://skia-review.googlesource.com/127133
Reviewed-by: Ravi Mistry <9fa2e7438b8cb730f96b74865492597170561628@google.com>
Commit-Queue: Ravi Mistry <9fa2e7438b8cb730f96b74865492597170561628@google.com>

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