common: Add a skip_before arg to the publish series script

[EbonJaeger]

Summary

Adds an argument to set a commit in the build order to skip to when pushing a stack.

Test Plan

Note that the following plan requires changes in infrastructure-tooling. Both of these changes should be merged together.

1. Merge a packaging PR with multiple builds.
2. Run the following command:

   go-task infra:build-pr -- -s 1 9868

3. See that the first build in the list will be skipped.
4. Run it again without -s 1 and see that no builds will be skipped.
5. Run it with -s bob and see that it tells me invalid number.

Checklist

• Package was built and tested against unstable
• This change could gainfully be listed in the weekly sync notes once merged
• I agree to license this contribution and all my previous contributions under the licensing terms in LICENSE.md and have the power and authority to grant those licenses.

[EbonJaeger]

The failing lint is not from code modified in this PR.

[HarveyDevel]

LGTM, thanks!