Description:
It would be nice to have the option to restore only and not save.

Justification:
In bigger repos, it's easy to hit the 10gb cache limit. Not caching in PRs can help with this.
Right now, I have to manually delete caches to help keep the caches on main alive.

Are you willing to submit a PR?

References

actions/toolkit#1308
Swatinem/rust-cache#95 (has a save-if option https://github.com/Swatinem/rust-cache#example-usage)