Configurable cache action

GitHub's cache is great if you're using GitHub hosted runners, but the cache heavily drops off in performance when you're using something else.

There are other cache providers that are fully compatible with `actions/cache`, but semantically work differently. For example: https://github.com/runs-on/cache

Would it be possible to support these caches? I think two flags would make sense:

1. the cache action label
2. additional arguments to pass into `with` block

Start at the GitHub Action's declared inputs and entry point, then trace how the cache action is selected. Compare the requested cache action label and additional `with` arguments with the existing configuration. Done means both options are supported and their behavior is verified by the repository's existing checks.

Written by the indexing model from the issue text.