Add ConnectivityConstraintTest to known failures

ConnectivityConstraintTest was inadvertently removed from the
blacklist in commit 015a287beb01 ("resolved conflicts for merge of
362fdcb7 to master").  It's still broken, so add it back.

Bug: 18117279
Change-Id: Icfab870c7c449a05829646c4179f4a13da588fc4
1 file changed