Unimplemented on Purpose/Problematic Exercises for a Track for 48in24

Per this discussion on Discord:

How might we (briefly!) annotate or note for students and/or implementers that a particular exercise has not been implemented on a track on purpose? I don’t want to create a bunch of extra work, but I also don’t want to field lots of questions if I can avoid it. :smile:

…and for some tracks there are problematic exercises that may be implemented, but they’re not really ideal. One such for Python is Yatch, which a ton of students have solve in a very problematic way by assigning names to lambdas.

Use the foregone key: config.json | Exercism's Docs