message: Add const
diff: @@ -292,7 +292,7 @@ void MavlinkCommandSender::do_work()
  {
  std::lock_guard<std::mutex> lock(_sent_commands_mutex);
  - auto was_inserted =
  + const auto was_inserted =
  _sent_commands.insert(std::make_pair(work->mavlink_command, work)).second;
  // The command is inserted in the list only if another command with the same id does
  