Add Add await fix for for_in_of_invalid_type when Future<Iterable>/Stream

[FMorschel]

Consider:

Future<void> foo(Future<List<int>> future) async {
  final controller = StreamController<int>();
  for (final i in controller.stream) {}
  for (final l in future) {}
}

For both cases, we could have the Add await fix. The first case only needs to insert it before for.

[FMorschel]

Here is the CL https://dart-review.googlesource.com/c/sdk/+/425540