CBLT-319:  triggered iOS jobs have build number different than job number

Change-Id: I76affe700c32decf37b0dfb6cea70dc842227d1a
Reviewed-on: http://review.couchbase.org/39325
Reviewed-by: Philip Labee <philip@couchbase.com>
Tested-by: Philip Labee <philip@couchbase.com>