Switch the pre-commit hook used to run `shellcheck`

[mcdonnnj]

🗣 Description

This pull request switches the pre-commit hook used to run shellcheck from detailyang/pre-commit-shell to shellcheck-py/shellcheck-py.

💭 Motivation and context

The new hook actually bundles the binary releases from shellcheck into a Python package that is used for the hook. This will ensure that we are always using the same version of shellcheck when linting since individual distributions and the GitHub Actions runners may update at different times..

🧪 Testing

Automated tests pass. I had @dav3r confirm that the hook works on his ARM Mac (shellcheck has limited binaries available for macOS).

✅ Pre-approval checklist

• [x] This PR has an informative and human-readable title.
• [x] Changes are limited to a single goal - eschew scope creep!
• [x] All relevant type-of-change labels have been added.
• [x] I have read the CONTRIBUTING document.
• [x] These code changes follow cisagov code standards.
• [x] All new and existing tests pass.

[jsf9k]

I done tried it and it done worked on my dang machine! :shipit:

I think that should be "dang ol' machine". :laughing:

[dav3r]

I done tried it and it done worked on my dang machine! :shipit:

I think that should be "dang ol' machine". 😆

I had "ole" in there originally, but it didn't (dun) look right. Definitely should've gone with "ol'" - missed opportunity.