Doc confusion: no instance of the proposed Functor in "type lambda gotchas"

[rossabaker]

In Type Lambda gotchas:

In these cases you should prefer the lambda syntax, which would be written as:

Functor[Lambda[a => Future[List[a]]]]

The documentation doesn't explicitly refer to Cats' Functor, but most people are going to assume that, and Cats provides no such functor out of the box.