[skip ci]Fix delete node comment lint (#9717)

Signed-off-by: Ngodchen <qingxiang.chen@zilliz.com>

internal/datanode/flow_graph_delete_node.go

@@ -46,7 +46,7 @@ type deleteNode struct {
 	minIOKV     kv.BaseKV
 }
 
-// BufferData buffers insert data, monitoring buffer size and limit
+// DelDataBuf buffers insert data, monitoring buffer size and limit
 // size and limit both indicate numOfRows
 type DelDataBuf struct {
 	delData *DeleteData