SC colo needs to use public URL to change default job param

Change-Id: Ied68431697f3af76311143c90f88e6e54a16dc02
Reviewed-on: http://review.couchbase.org/40734
Reviewed-by: Chris Hillery <ceej@couchbase.com>
Tested-by: Chris Hillery <ceej@couchbase.com>