[submodule_update] Parse flags
This was omitted when migrating from google3 because flag parsing was
handled implicitly by the google3-specific `google.Init()` function.
This caused the tool to always think that no command was specified.
Bug: 320755417
Change-Id: Ic9ee8c1a48aeeaea7c27128bc38f85ddd43c40cf
Reviewed-on: https://fuchsia-review.googlesource.com/c/infra/infra/+/980372
Fuchsia-Auto-Submit: Oliver Newman <olivernewman@google.com>
Commit-Queue: Auto-Submit <auto-submit@fuchsia-infra.iam.gserviceaccount.com>
Reviewed-by: Rob Mohr <mohrr@google.com>
1 file changed
