ndb - make sure to drop table at end ndb_update

mysql-test/r/ndb_update.result

@@ -11,3 +11,4 @@ pk1	b	c
 0	1	1
 1	2	2
 2	3	3
+drop table t1;

mysql-test/t/ndb_update.test

@@ -20,3 +20,5 @@ CREATE TABLE t1 (
 INSERT INTO t1 VALUES (0, 0, 1),(1,1,2),(2,2,3);
 UPDATE t1 set b = c;
 select * from t1 order by pk1;
+
+drop table t1;