Fix forwarding in ParkingLot<T>::WaitNode ctor
Fix forwarding in ParkingLot<T>::WaitNode ctor

Summary: [Folly] Fix forwarding in `ParkingLot<T>::WaitNode` ctor.

Reviewed By: aary

Differential Revision: D9478603

fbshipit-source-id: 1da4c985bee7293356b1f5e1b43678282703b8ce

facebook/folly,facebook/folly,facebook/folly,facebook/folly,facebook/folly