Improve output of `lint` script in CI

[mkannwischer]

If linting is failing in CI, the CI output is really not useful.
See for example here: https://github.com/pq-code-package/mldsa-native/actions/runs/23435221183/job/68171478451

Now one has to expand all sections to see the actual error.
We should improve this so that the error is immediately shown.