CBQE-1899: add connection_timeout to queries performed in biXDCR test

Change-Id: Ie02a5fc1e43e73ffcc56c4a955f357e9453c1adb
Reviewed-on: http://review.couchbase.org/32711
Reviewed-by: Sangharsh Agarwal <sangharsh.agarwal@globallogic.com>
Tested-by: Iryna Mironava <irynamironava@yandex.ru>