Do something about the big rust build overhead

[tlater-famedly]

We have a lot of cargo extensions that are installed in this docker image. Building them takes 20-30 minutes, this is one of our longest (and probably most expensive) CI builds.

We should consider using cargo-binstall to escape this, since pre-built binaries are available for practically all our inputs. Security implications exist, but there are probably easier ways to break our supply chain.

Failing that, we should probably at least consider using the faster builders for some workflows.

[bitfl0wer]

A custom workflow could be made, which builds whitelisted versions of crates and publishes them into an internal cargo-binstall repository. Our other CIs could then use cargo-binstall, pointed to this repository. This way, we know for sure what is being installed on our runners and costs/resource usage could come down dramatically