Disabled hashkey test due to non-determinisim.

Change-Id: I84936505eff3f1dd37a98d73d8a8aebcf174a19e
Reviewed-on: http://review.couchbase.org/36076
Reviewed-by: Mark Nunberg <mnunberg@haskalah.org>
Tested-by: Brett Lawson <brett19@gmail.com>