vpython's default verification does not yet include this platform,
so this allows us to ensure that depot_tools vpython specs stay mac-arm64
compatible.

Bug: 1235841, 1225523, 1205263
Change-Id: I9445319d75ced4a18f25e4eb5262f96824232498
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/tools/depot_tools/+/3144238
Commit-Queue: Brian Ryner <bryner@google.com>
Reviewed-by: Dirk Pranke <dpranke@google.com>