[opt](pipeline) Return InternalError to FE instead of doing a useless…

… DCHECK in ExecNode apache#27035

Effect: Client will see error message like below when BE meeting plan logical error.

RROR 1105 (HY000): errCode = 2, detailMessage = ([xxx]())[CANCELLED]Logical error during processing VNewOlapScanNode(dr_case_tag), output of projections 2 mismatches with exec node output 3

be/src/exec/exec_node.cpp

@@ -559,7 +559,14 @@ Status ExecNode::do_projections(vectorized::Block* origin_block, vectorized::Blo
 
     if (rows != 0) {
         auto& mutable_columns = mutable_block.mutable_columns();
-        DCHECK(mutable_columns.size() == _projections.size());
+
+        if (mutable_columns.size() != _projections.size()) {
+            return Status::InternalError(
+                    "Logical error during processing {}, output of projections {} mismatches with "
+                    "exec node output {}",
+                    this->get_name(), _projections.size(), mutable_columns.size());
+        }
+
         for (int i = 0; i < mutable_columns.size(); ++i) {
             auto result_column_id = -1;
             RETURN_IF_ERROR(_projections[i]->execute(origin_block, &result_column_id));