CCBC-1361: allow "_default._default" collection for pre-collections servers
CCBC-1361: allow "_default._default" collection for pre-collections servers

Change-Id: If84b719996cc07e2e8cbcc07d03f3229aa782992
Reviewed-on: http://review.couchbase.org/c/libcouchbase/+/144136
Reviewed-by: Brett Lawson <c8c4369773d7d7226e031f0c4af62e3f38a08510@gmail.com>
Tested-by: Build Bot <80754af91bfb6d1073585b046fe0a474ce868509@couchbase.com>

couchbase/libcouchbase,kojiromike/libcouchbase,kojiromike/libcouchbase,couchbase/libcouchbase,kojiromike/libcouchbase,couchbase/libcouchbase,couchbase/libcouchbase,couchbase/libcouchbase,couchbase/libcouchbase,kojiromike/libcouchbase,couchbase/libcouchbase