don't expect replies from upr window update requests

Change-Id: I4fc8316256a2ffcb213d81ec1a9cb7d1ef92cf90
Reviewed-on: http://review.couchbase.org/38996
Tested-by: Aliaksey Kandratsenka <alkondratenko@gmail.com>
Reviewed-by: Aliaksey Artamonau <aliaksiej.artamonau@gmail.com>