async<> call with calltype

TUniqueFunction<int()> Task = ]()->int { return 123; };
auto Result = Async<int>(EAsyncExecution::Thread, Task);

if I remove <int> from Async, it will compile ok, but when I put it back, I got compile error.
for UE 4.23

i have same problem with <void>

Yea the function signature changed and the call type is inferred now.