Ignore motion mark svg slight pixel mismatches in mtltestprecompile

Change-Id: Ia5a11580a793226253e2e294f6c43aa76fa97e8f
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/441882
Commit-Queue: Brian Salomon <bsalomon@google.com>
Commit-Queue: Jim Van Verth <jvanverth@google.com>
Auto-Submit: Brian Salomon <bsalomon@google.com>
Reviewed-by: Jim Van Verth <jvanverth@google.com>
2 files changed