suppress leak-detective stderr output in ipsec pool

testing/tests/ikev2/ip-pool-db/posttest.dat

@@ -4,5 +4,5 @@ dave::ipsec stop
 moon::/etc/init.d/iptables stop 2> /dev/null
 carol::/etc/init.d/iptables stop 2> /dev/null
 dave::/etc/init.d/iptables stop 2> /dev/null
-moon::ipsec pool --del bigpool
+moon::ipsec pool --del bigpool 2> /dev/null
 moon::rm /etc/ipsec.d/ipsec.*