Parse --manifest json output produced by an external clippy command

[Luni-4]

In https://github.com/burn-rs/burn we use scripts to maintain locally and CI checks coherently and with the minimum maintenance effort.

Would it be possible to add an option that does not run the cargo clippy present in the action, but just takes the --manifest-path json output produced by an external clippy action and parses that?