infra/tools/protoc does not exist for mac-arm64, use amd64 instead.
infra/tools/protoc does not exist for mac-arm64, use amd64 instead.

It looks like this is due to be fixed upstream soon and we can
remove the workaround once we've moved to the new protoc release.
In the meantime, this will work via Rosetta.

Change-Id: I49875546cbda1a2d2450033cb0d63821833047e0
Reviewed-on: https://chromium-review.googlesource.com/c/infra/luci/recipes-py/+/3435205
Auto-Submit: Brian Ryner <388ea68edb4d8f934960c128120aee09a8f854bf@google.com>
Reviewed-by: Robbie Iannucci <40f3d43a28ebae3cb819288542e1c84d73d962d5@chromium.org>
Commit-Queue: Robbie Iannucci <40f3d43a28ebae3cb819288542e1c84d73d962d5@chromium.org>

luci/recipes-py,luci/recipes-py