Just like with rust/coreutils, compare with the GNU implementation and highlight improvements and regressions

This is done here:
https://github.com/uutils/coreutils/blob/main/.github/workflows/GnuTests.yml
and
https://github.com/uutils/coreutils/blob/main/.github/workflows/GnuComment.yml

we are publishing results on:
https://github.com/uutils/coreutils-tracking/

Note that we also have:
https://github.com/uutils/findutils-tracking/
