message: Remove the unnecessary const var
diff: @@ -410,13 +410,12 @@ void NcclManager::AddParticipant(std::unique_ptr<Participant> participant,
  CollectiveType collective_type,
  ncclRedOp_t reduction_op) {
  Collective* to_run = nullptr;
  - DataType data_type_val;
  + DataType data_type;
  if (participant->input != nullptr) {
  - data_type_val = participant->input->dtype();
  + data_type = participant->input->dtype();
  } else {
  - data_type_val = participant->output->dtype();
  + data_type = participant->output->dtype();
  }
  - const DataType data_type = data_type_val;
  {
  mutex_lock l(mu_);
  auto collective_it = collectives_.find(context.collective_key);
  