CLOUDSTACK-4065: db upgrade - when insert placeHolder nic for Shared networks, always mark this nic as non-default explicitly
remove hardcoded vlan for shared network test

use a vlan outside of the vlans managed by cloudstack.

Signed-off-by: Prasanna Santhanam <tsp@apache.org>
(cherry picked from commit 7eefeab957e7b2a904a2f5ec1ce2a2624587eb9e)