Bug#42891: Tests cleanup

Fix for backport into mysql-5.1-rep+2

mysql-test/suite/rpl/r/rpl_heartbeat.result

 reset master;
+set @restore_slave_net_timeout= @@global.slave_net_timeout;
 set @@global.slave_net_timeout= 10;
 Warnings:
 Warning	1624	The currect value for master_heartbeat_period exceeds the new value of `slave_net_timeout' sec. A sensible value for the period should be less than the timeout.
@@ -140,4 +141,5 @@ Variable_name	Slave_heartbeat_period
 Value	0.500
 A heartbeat has been received by the slave
 drop table t1;
+set @@global.slave_net_timeout= @restore_slave_net_timeout;
 End of tests

mysql-test/suite/rpl/t/rpl_heartbeat.test

@@ -16,6 +16,7 @@ connection master;
 reset master;
 
 connection slave;
+set @restore_slave_net_timeout= @@global.slave_net_timeout;
 set @@global.slave_net_timeout= 10;
 
 ###
@@ -161,6 +162,7 @@ drop table t1;
 
 #connection slave;
 sync_slave_with_master;
+set @@global.slave_net_timeout= @restore_slave_net_timeout;
 
 
 --echo End of tests