WLS on AKS: Do not provision public IP for Ubuntu machine.

[galiacheng]

The WLS on AKS offering relies on an Ubuntu machine to build the WLS image, which requires the creation of a public IP.

If a subscription has the policy "Network interfaces should not have public IPs" assigned, the public IP provisioning triggers this policy. This results in the denial of resource deployment and causes the WLS on AKS deployment to fail.

This issue is to figure out whether we can use the Ubuntu machine without a public IP.