Add verify-pr-builder hook

[KyleFromNVIDIA]

Add hook to verify that the pr-builder job is set up correctly.

This supersedes the rapids-check-pr-job-dependencies tool. The tool only does static analysis and does not depend on the GitHub environment. Such a check can be done on the developer's machine, while also ensuring that the lists are sorted properly, and automatically fixing any mistakes.

[jameslamb]

For your consideration.... the rapidsai/shared-workflows checks and gha-tools scripts are used by other repos outside of RAPIDS.

(GitHub Search)

Some examples:

• NVIDIA/numbast (code link)
• NVIDIA/numba-cuda (code link)
• nv-morpheus/Morpheus (code link)

If we pair a change like this with dropping the corresponding code that currently comes for free with just using shared-workflows (shared-workflows code link), then at a minimum I think we should roll out this hook to those other repos.

I'm weakly against this proposal.

benefits:

• slightly less wasted CI and developer time, via finding out locally that some GitHub Actions config changes are needed (instead of only finding out after a push + CI run)
• simplifies development in gha-tools repo
• simplifies the checks workflow from shared-workflows slightly

costs:

• elevated risk of silently missing pr-builder dependencies in new repos (as a result of now needing to opt in to this validation via a pre-commit hook)
• development work of rolling out the hook to all repos currently using rapidsai/shared-workflows
• increased complexity and maintenance burden here in pre-commit-hooks

Based on those, I think the costs outweigh the benefits and this should be left alone. But I don't feel so strongly enough about this to block this PR.