[pipeline](task_queue) remove disable steal in task queue to speed up query (#21692)

TPCH Q9

before: 2.74s
after: 2.33s

be/src/pipeline/task_queue.cpp

@@ -34,9 +34,6 @@ PipelineTask* SubTaskQueue::try_take(bool is_steal) {
         return nullptr;
     }
     auto task = _queue.front();
-    if (!task->can_steal() && is_steal) {
-        return nullptr;
-    }
     _queue.pop();
     return task;
 }