CBQE-0 Increase sleep after delete

Change-Id: I6571444220a96a585d85881d38648b87958bf044
Reviewed-on: http://review.couchbase.org/26554
Reviewed-by: Deepkaran Salooja <deepkaran.salooja@globallogic.com>
Tested-by: Deepkaran Salooja <deepkaran.salooja@globallogic.com>