union.result, union.test:

  a small fix for the test case


mysql-test/t/union.test:
  a small fix for the test case
mysql-test/r/union.result:
  a small fix for the test case

mysql-test/r/union.result

@@ -935,3 +935,4 @@ select 1 union select 2;
 1
 1
 2
+set sql_select_limit=1;

mysql-test/t/union.test

@@ -502,4 +502,5 @@ set sql_select_limit=1;
 select 1 union select 2;
 (select 1) union (select 2);
 (select 1) union (select 2) union (select 3) limit 2;
+set sql_select_limit=1;