Adding a note on Property-Based Testing in the TDD skill

[dubzzz]

Property-Based Testing is a well suited way to assess the What of an
algorithm. The aim of this technique is to abstract the checks from hardcoded
values and rather check invariants. Having it as a recommendation when thinking
about tests would probably be a good addition.

I could eventually link some guidelines I wrote on when PBT pays off versus when an example test is the better tool. Giving some pointers about good usages for such technique would be awesome for designing better tests.

About me: I'm the author of fast-check, the
leading Property-Based Testing library in JavaScript. I'm a
strong believer that Property-Based Testing is not as used and recommended as
it should be.