[gold] Fix diffcalculator tests with new version
[gold] Fix diffcalculator tests with new version

Bug: skia:10582
Change-Id: I7bc747de8dab2f77a1f0d87861f2b1cebafdbb48
Reviewed-on: https://skia-review.googlesource.com/c/buildbot/+/370547
Reviewed-by: Kevin Lubick <7cdab2cfab351f23814786ba39716e90eed69047@google.com>
Commit-Queue: 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