typing: add type hints to pycompat.maplist() The typeshed hints define 5 overloads with an increasing number of parameters on the passed function, and then a catchall that ignores the argument list on the passed function and allows an `*iterators` arg. All of our uses are fulfilled by the 1 function + 1 iterable overload, but add the second overload as a hint in case it's needed in the future.