Caches Rust for Run Linters CI (#71487)
Caches Rust for Run Linters CI (#71487)

## About The Pull Request

Hey there,

It's on the tin, we just cache the whole Rust installation to use over
multiple workflows. Without this, it would take up to _five minutes per
linters workflow run_ to install the whole fucking rust toolchain/crate
dependencies (ref:
https://github.com/san7890/bruhstation/actions/runs/3536980337/jobs/5936542571
).

Now with the cache, it's now down to approximately one minute, thirty
seconds after it's able to pull a cached rust installation (ref:
https://github.com/san7890/bruhstation/actions/runs/3537002138/jobs/5936585526
). More than half is very good, and frees up valuable Github Runners
slots sooner!

I've also always seen linters as that rapid check to immediately call
you out whenever you screw up in a PR, and it taking four minutes sorta
lessens that immediate: "HEY, LISTEN!" aspect
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