[refactor] replace boost smart ptr with stl (#6856)

1. replace all boost::shared_ptr to std::shared_ptr
2. replace all boost::scopted_ptr to std::unique_ptr
3. replace all boost::scoped_array to std::unique<T[]>
4. replace all boost:thread to std::thread

be/src/exec/select_node.cpp

@@ -27,7 +27,7 @@ namespace doris {
 
 SelectNode::SelectNode(ObjectPool* pool, const TPlanNode& tnode, const DescriptorTbl& descs)
         : ExecNode(pool, tnode, descs),
-          _child_row_batch(NULL),
+          _child_row_batch(nullptr),
           _child_row_idx(0),
           _child_eos(false) {}