porting findutils testing to use uutests

[hz2]

closes #537

[hz2]

creating a draft to get feedback before porting all tests

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 87.66%. Comparing base (69b32a9) to head (aeb2429).
⚠️ Report is 74 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #541      +/-   ##
==========================================
+ Coverage   87.49%   87.66%   +0.17%     
==========================================
  Files          31       31              
  Lines        6815     6893      +78     
  Branches      321      324       +3     
==========================================
+ Hits         5963     6043      +80     
+ Misses        621      617       -4     
- Partials      231      233       +2     

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.

🚀 New features to boost your workflow:

• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.

[sarnobat]

@hz2 - are you still working on this? I'd like to know if you have the bandwidth to collaborate with me or whether it's better I just contribute directly.

[sarnobat]

@hz2 - are you still working on this? I could try to resolve the conflicts but if you're not in a place to contribute, I'll do it independently.

[sylvestre]

@sarnobat please go ahead