removeUser method Null safety
Removes the current user
Implementation
Future<void> removeUser() async {
  if (currentUser.isValid) await _syncController.delete(currentUser);
  model(User.empty());
}Removes the current user
Future<void> removeUser() async {
  if (currentUser.isValid) await _syncController.delete(currentUser);
  model(User.empty());
}