Fix regression for new DROP RULE syntax.

src/test/regress/expected/alter_table.out

@@ -734,6 +734,6 @@ select * from def_view_test;
  45 | view_default
 (7 rows)
 
-drop rule def_view_test_ins;
+drop rule def_view_test_ins on def_view_test;
 drop view def_view_test;
 drop table def_test;

src/test/regress/sql/alter_table.sql

@@ -568,6 +568,6 @@ alter table def_view_test alter column c2 set default 'view_default';
 insert into def_view_test default values;
 select * from def_view_test;
 
-drop rule def_view_test_ins;
+drop rule def_view_test_ins on def_view_test;
 drop view def_view_test;
 drop table def_test;