[gold] Quieten "npx mocha" output by removing console.log() statement.
[gold] Quieten "npx mocha" output by removing console.log() statement.

Change-Id: Ibded63abb962abb60023e13246b57f052a067074
Reviewed-on: https://skia-review.googlesource.com/c/buildbot/+/284077
Auto-Submit: Leandro Lovisolo <f558143c2568be8d55575d13f30a1fc5cb8009d5@google.com>
Commit-Queue: Kevin Lubick <7cdab2cfab351f23814786ba39716e90eed69047@google.com>
Reviewed-by: Kevin Lubick <7cdab2cfab351f23814786ba39716e90eed69047@google.com>

google/skia-buildbot,google/skia-buildbot,google/skia-buildbot,google/skia-buildbot,google/skia-buildbot,google/skia-buildbot,google/skia-buildbot,google/skia-buildbot