Add explicit vpython verification tags which include mac-arm64.

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>

.vpython

 python_version: "2.7"
 
+# The default set of platforms vpython checks for does not yet include mac-arm64.
+# Setting `verify_pep425_tag` to the list of platforms we explicitly must support
+# allows us to ensure that vpython specs stay mac-arm64-friendly
+verify_pep425_tag: [
+    {python: "cp27", abi: "cp27mu", platform: "manylinux1_x86_64"},
+    {python: "cp27", abi: "cp27mu", platform: "linux_arm64"},
+    {python: "cp27", abi: "cp27mu", platform: "linux_armv6l"},
+
+    {python: "cp27", abi: "cp27m", platform: "macosx_10_10_intel"},
+    {python: "cp27", abi: "cp27m", platform: "macosx_11_0_arm64"},
+
+    {python: "cp27", abi: "cp27m", platform: "win32"},
+    {python: "cp27", abi: "cp27m", platform: "win_amd64"}
+]
+
 # Used by:
 #   auth.py
 #   gerrit_util.py

.vpython3

 python_version: "3.8"
 
+# The default set of platforms vpython checks for does not yet include mac-arm64.
+# Setting `verify_pep425_tag` to the list of platforms we explicitly must support
+# allows us to ensure that vpython specs stay mac-arm64-friendly
+verify_pep425_tag: [
+    {python: "cp38", abi: "cp38", platform: "manylinux1_x86_64"},
+    {python: "cp38", abi: "cp38", platform: "linux_arm64"},
+    {python: "cp38", abi: "cp38", platform: "linux_armv6l"},
+
+    {python: "cp38", abi: "cp38", platform: "macosx_10_10_intel"},
+    {python: "cp38", abi: "cp38", platform: "macosx_11_0_arm64"},
+
+    {python: "cp38", abi: "cp38", platform: "win32"},
+    {python: "cp38", abi: "cp38", platform: "win_amd64"}
+]
+
 # Used by:
 #   auth.py
 #   gerrit_util.py