message: Return Timeout code when timing out, instead of ConnectionError
diff: @@ -307,7 +307,7 @@ void MavlinkCommandSender::receive_timeout(const CommandIdentification& identifi
  LogErr() << "Retrying failed (" << work->identification.command << ")";
  temp_callback = work->callback;
  - temp_result = {Result::ConnectionError, NAN};
  + temp_result = {Result::Timeout, NAN};
  _work_queue.erase(it);
  break;
  }
  