CBQE-927: minor changes in newupgradetests

Change-Id: Iaf4487c7bc6436bd03ab38eaf832fc930481d520
Reviewed-on: http://review.couchbase.org/23657
Reviewed-by: Andrei Baranouski <andrei.baranouski@gmail.com>
Tested-by: buildbot <build@couchbase.com>