CBQE-928: fix online_consequentially_upgrade

Change-Id: I9e0c047b8019c3b2c40319e582c12a0fdbd3ce7b
Reviewed-on: http://review.couchbase.org/24233
Reviewed-by: Andrei Baranouski <andrei.baranouski@gmail.com>
Tested-by: Andrei Baranouski <andrei.baranouski@gmail.com>