Update required checks: Allow authenticating via the GitHub CLI

[henrymercer]

We no longer run this script within Actions for security reasons, and when running locally we can authenticate with the GitHub CLI instead of a PAT.

Merge / deployment checklist

• Confirm this change is backwards compatible with existing workflows.
• Confirm the readme has been updated if necessary.
• Confirm the changelog has been updated if necessary.

[adityasharad]

Maybe still keep a log warning, and a comment that this script is meant for interactive use, not as an unattended script. Otherwise in an unattended setting it will hang when it waits for you to authenticate.

[henrymercer]

I don't really like the idea of logging warnings when everything's fine, particularly when the main use case of this script is running from a dev machine. However I can see the benefit in preventing an unattended script from hanging. I've switched to checking gh auth status at the start of the script instead. This returns a non-zero exit code if the user isn't authed.

[aeisenberg]

Forgot to leave this comment earlier.