MB-4049 limited autofailover timeout by 1hr

Change-Id: I6e7a173c61e785239b7b943b45d255290b49d5de
Reviewed-on: http://review.couchbase.org/27616
Tested-by: Artem Stemkovski <artem@couchbase.com>
Reviewed-by: Aliaksey Artamonau <aliaksiej.artamonau@gmail.com>