CBD-1425:  WORKSPACE env.var. already defined !

Change-Id: I87cbef1e04ac3eb97b13cd07186147cfa30c313d
Reviewed-on: http://review.couchbase.org/40442
Reviewed-by: Philip Labee <philip@couchbase.com>
Tested-by: Philip Labee <philip@couchbase.com>