MDEV-33661 MENT-1591 Fix spider/bugfix.mdev_28856 because of MDEV-29718.

The failure should be table not found, rather than no spider same
server link

storage/spider/mysql-test/spider/bugfix/r/mdev_28856.result

@@ -5,6 +5,8 @@ for master_1
 for child2
 for child3
 set spider_same_server_link=1;
+set @old_spider_same_server_link=@@global.spider_same_server_link;
+set global spider_same_server_link=1;
 CREATE SERVER srv FOREIGN DATA WRAPPER mysql
 OPTIONS (SOCKET "$MASTER_1_MYSOCK", DATABASE 'test',user 'root');
 # testing monitoring_*
@@ -173,6 +175,7 @@ max(d)
 93
 drop table t1, t2;
 drop server srv;
+set global spider_same_server_link=@old_spider_same_server_link;
 for master_1
 for child2
 for child3

storage/spider/mysql-test/spider/bugfix/t/mdev_28856.test

@@ -10,6 +10,9 @@
 # This test covers some table params under consideration for inclusion
 # in the engine-defined options to be implemented in MDEV-28856.
 set spider_same_server_link=1;
+set @old_spider_same_server_link=@@global.spider_same_server_link;
+set global spider_same_server_link=1;
+
 evalp CREATE SERVER srv FOREIGN DATA WRAPPER mysql
 OPTIONS (SOCKET "$MASTER_1_MYSOCK", DATABASE 'test',user 'root');
 
@@ -153,6 +156,7 @@ select max(d) from t1;
 drop table t1, t2;
 
 drop server srv;
+set global spider_same_server_link=@old_spider_same_server_link;
 
 --disable_query_log
 --disable_result_log