MDEV-17096 Pushdown of simple derived tables to storage engines

Made the setting of the system variable federated_pushdown at
the default connection.

mysql-test/suite/federated/federatedx_create_handlers.result

@@ -4,6 +4,8 @@ connection master;
 CREATE DATABASE federated;
 connection slave;
 CREATE DATABASE federated;
+connection default;
+set global federated_pushdown=1;
 connection slave;
 DROP TABLE IF EXISTS federated.t1;
 Warnings:
@@ -301,6 +303,7 @@ DROP TABLE federated.t1, federated.t2, federated.t3;
 connection slave;
 DROP TABLE federated.t1, federated.t2;
 connection default;
+set global federated_pushdown=0;
 connection master;
 DROP TABLE IF EXISTS federated.t1;
 DROP DATABASE IF EXISTS federated;

mysql-test/suite/federated/federatedx_create_handlers.test

 --source have_federatedx.inc
 --source include/federated.inc
 
+connection default;
+
 set global federated_pushdown=1;
 
 connection slave;
@@ -153,6 +155,7 @@ DROP TABLE federated.t1, federated.t2;
 
 connection default;
 
+set global federated_pushdown=0;
+
 source include/federated_cleanup.inc;
 
-set global federated_pushdown=0;