change the test to reflect the fix in #duckdb/14171

Author: Tishj

test/sql/sql_reduce.test

@@ -48,7 +48,7 @@ INSERT INTO tbl (VALUES (1))
 INSERT INTO tbl (VALUES (1, 2))
 INSERT INTO tbl (VALUES (2))
 INSERT INTO tbl SELECT *
-INSERT INTO tbl SELECT NULL FROM (VALUES (1, 2))
+INSERT INTO tbl SELECT NULL FROM (VALUES (1, 2)) AS valueslist
 INSERT INTO tbl SELECT NULL FROM (VALUES (1, 2)) AS valueslist
 
 query I