Disabling rpl_heartbeat_timestamp in valgrind and parallel mode

Summary:
This is a time dependent testcase so it doesn't work well with
these options

Squash with: D5006919

Reviewed By: lth

Differential Revision: D5131105

fbshipit-source-id: d39c930

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

@@ -7,6 +7,9 @@
 # slave_2 is between 0 and heartbeat period. We then kill the master and
 # check if the lag on slave_2 keeps increasing.
 
+source include/not_valgrind.inc;
+source include/not_parallel.inc;
+
 let $rpl_server_count= 3;
 let $rpl_topology= 1->2->3;
 source include/rpl_init.inc;