Thanks for taking the time to answer. I'm a newcomer at Codewars so I probably need to tune in with the philosophy. That said, I don't understand why people would want to cheat the solutions (maybe to show a "strong" profile in a job interview?). In the end they are lying to themselves.

Nothing better than delegating on the standard libraries! ;)

OK, I know this is not strict unit testing, but using random data to validate solutions might leave room for incompleteness (either the solution or the validation code).
Fraud can come in a wide variety of forms (copy-pasting from other sites, hardcoding results, AI generated solutions...). Should the katas codebase quality be impacted because of this?
Regulatory measures should be separated from the kata's logic. Otherwise, in the long run, the code base will be formed with (in this case) a lot of non-repeatable tests (which, IMHO, is not very high-quality code, so to say :) ).
Perhaps users should have the means to mark other's solutions as "hardcoded", with an impact on "honor".

Random tests defeat one of the main purposes of testing: repeatability. Codewars should forbid use of random tests (unless VERY well justified). In this specific kata I don't see the justification at all.