VM Image Builder Templates Should Use Private Link

Description:

Audit VM Image Builder templates that do not have a virtual network configured. When a virtual network is not configured, a public IP is created and used instead, which may directly expose resources to the internet and increase the potential attack surface.

Solution/Reference: 

To enable private link connection when building VM Image Builder templates, add vnetConfig to templates.

For details, see http://aka.ms/azvmimagebuildertmplref.