Enable all Mtl tests

Bug: skia:8243
Change-Id: Ic95aefa7f08ff3f931923dd57faab0e2ceeb03e4
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/207309
Reviewed-by: Greg Daniel <egdaniel@google.com>
Commit-Queue: Jim Van Verth <jvanverth@google.com>
2 files changed