Micro::Case::Result#on_unknow

[serradura]

If a result can’t be handled (imagine a flow where the result type wasn’t handled or some use case where none of its Failure or Success definition was intercepted), this hook will be triggered and the user can log, measure it for learning about this unexpected behavior.

This feature was inspired by https://youtu.be/qoriifl-z3Q

Thanks @avdi!