Break once an empty slot has been found in SimpleMQTTServerMessageThread::assignConnections()

CollectAgent/simplemqttserverthread.cpp

@@ -422,6 +422,7 @@ void SimpleMQTTServerMessageThread::assignConnections()
         cout << "Assigned connection  (" << this << ", " << i << ", " << fds[i].fd << ")...\n";
         coutMtx.unlock();
 #endif
+        break;
       }
     }
   }