server : fix incoming tasks not process in order (#15395)

tools/server/server.cpp

@@ -1729,7 +1729,7 @@ struct server_queue {
     void pop_deferred_task() {
         std::unique_lock<std::mutex> lock(mutex_tasks);
         if (!queue_tasks_deferred.empty()) {
-            queue_tasks.emplace_back(std::move(queue_tasks_deferred.front()));
+            queue_tasks.emplace_front(std::move(queue_tasks_deferred.front()));
             queue_tasks_deferred.pop_front();
         }
         condition_tasks.notify_one();