Update renovate.json and ci script

Addresses: #81 (closed)

I started looking into the `renovate.json` script and changed it to ignore the dependencies we noted in !283 (merged)

From there I started wondering about improving the ci script and whether or not we could improve any of the other things mentioned by the browser team there. I started with some simple additional tests like calling cargo fmt and cargo clippy and noticed that there was also a test for cargo audit so I included that as well and fixed up the resulting errors. Maybe there are additional things we could check that would be useful for browser integration going forward.

This MR also pulls in the scripts from arti which are definitely overkill since we only need one at the moment, but perhaps it would make sense to use others as well.

I need to fix up this commit structure to be a bit less ridiculous before it's ready