Garage aka utils folder cleanup

[wendellpiez]

In the OSCAL repository, this commit goes some way to seeing to it that the repository contains only such resources as spark joy.

Committer Notes

This commit should partially satisfy #966. (Work on the Metaschema repository is also in order.)

All Submissions:

• Have you followed the guidelines in our Contributing document?
• Have you checked to ensure there aren't other open Pull Requests for the same update/change?
• Have you squashed any non-relevant commits and commit messages? [instructions]
• Do all automated CI/CD checks pass?

Changes to Core Features:

• Have you added an explanation of what your changes do and why you'd like us to include them?
• Have you written new tests for your core changes, as applicable?
• Have you included examples of how to use your new feature(s)?
• Have you updated all OSCAL website and readme documentation affected by the changes you made? Changes to the OSCAL website can be made in the docs/content directory of your branch.

[david-waltermire]

@wendellpiez I think this is ready to merge. If you'd like me to do so, please rebase this branch and mark it non-draft.