CBQE-2265 : Update replica read tests to run expiry pager for deleting expired items

Change-Id: I809555ff55937067953d2c9ad82e248f15b60dcc
Reviewed-on: http://review.couchbase.org/37650
Tested-by: buildbot <build@couchbase.com>
Reviewed-by: Iryna Mironava <irynamironava@yandex.ru>
Reviewed-by: Meenakshi Goel <meenakshi.goel@globallogic.com>
Tested-by: Meenakshi Goel <meenakshi.goel@globallogic.com>