CBQE-0 Increase sleep after delete

Change-Id: I2681c4883aa9225fe2616926fad53654a155a648
Reviewed-on: http://review.couchbase.org/26555
Reviewed-by: Deepkaran Salooja <deepkaran.salooja@globallogic.com>
Tested-by: Deepkaran Salooja <deepkaran.salooja@globallogic.com>