Cardano Updates

### Changes

- Add a script to check and add eol
- Add eol where required
- Add a CI step to enforce it

### Issues
fix #5014

### Changes

- Fix shebang in run.sh so it's usable on the mac
- Remove unused env vars in the main pipeline
- Warm up nix with `nix shell` and not `nix build` as `nix shell` is
invoked in the run.sh
- Remove buildkite level timeout in favor of run.sh internal timeout

### Issues

fix #5051

### Changes

- Fix shebang in run.sh so it's usable on the mac
- Remove unused env vars in the main pipeline
- Warm up nix with `nix shell` and not `nix build` as `nix shell` is
invoked in the run.sh
- Remove buildkite level timeout in favor of run.sh internal timeout

### Issues

fix #5051

Replace the use of custom (and duplicated) code with battle-tested
standard library function.
This is an alternative attempt at fixing #5045.

Replace the use of custom (and duplicated) code with battle-tested standard library
function.

Replace the use of custom (and duplicated) code with battle-tested standard library
function.