Make CI run faster

[fvictorio]

The EDR workflow takes more than 25 minutes to run. We should check if there's room for improvement here.

One easy gain is to remove the dependency between the tests and the "Check EDR" job. That would save some minutes, and the only downside is that we "waste" some computing time by running the tests when the build/lint fails.

We should also consider taking the slowest tests and only running them in main or during pre-release.

[Wodann]

There might be a simpler fix for this. We set the Cargo profile for tests to be optimised, but this means that builds take longer. We should see whether this tradeoff is worth it in CI/locally.

[alcuadrado]

I think the cache and solc changes in this PR can be extra relevant here: https://github.com/NomicFoundation/hardhat/pull/5184/files

[Xanewok]

I already looked into streamlining and speeding up local workflow as part of my onboarding (e.g. #499), so I'll take a quick look with a fresh pair of eyes if there's anything we can do to get the best bang for the buck on the Rust/Cargo side.