Exclude PromiseImageTextureReuseDifferentConfig from Metal bots

TBR=robertphillips@google.com

Change-Id: I4729364745cfe216423948df4a9f209a8d987059
Reviewed-on: https://skia-review.googlesource.com/c/184740
Reviewed-by: Brian Salomon <bsalomon@google.com>
Commit-Queue: Brian Salomon <bsalomon@google.com>
2 files changed