Troubleshoot forge fmt CI failures

[davidlaprade]

Failing here #82

Trying to figure out why. Does CI fail on a ~clean branch off of master?

[davidlaprade]

The issue was the foundry nightly warning. Disabling it fixed the problem.

I used this action to create a CI job that would allow me to SSH into the box to debug things in an environment with the failure. Once in the box, I wrote a rust script similar to the one that was failing and cargo built it, then ran it to see what step was actually failing. It was the forge fmt --check step. The only "error" in that step was the warning, so I tried silencing the warning with FOUNDRY_DISABLE_NIGHTLY_WARNING=1 and scopelint check started passing. This was the problem.

I've cherrypicked 385a775 onto #82 and will merge it there. Closing this out.