endDocumentDragGesture method
Ends a drag gesture that's simulated with the given gesture.
To end the drag gesture, the point is released from surface and then the pointer is removed from the gesture simulator.
Implementation
Future<void> endDocumentDragGesture(TestGesture gesture) async {
  await gesture.up();
  await gesture.removePointer();
  await pumpAndSettle();
}