CBQE-1407: fix failover tests on windows

Change-Id: Ic8113afcd032a0cb37b4eaf1e162b28afe54d93a
Reviewed-on: http://review.couchbase.org/28015
Reviewed-by: Andrei Baranouski <andrei.baranouski@gmail.com>
Tested-by: Andrei Baranouski <andrei.baranouski@gmail.com>