Allow multiple admin domains per Tenant

When upgrading to AMP 2.2 from 2.0 there is a multitenancy feature that adds some routing logic for the client requests (to the admin portal) to reach the correct Tenant in system-provider. This check on the hostname value in the request means that if multiple routes were configured to point to system-provider in 2.0 they will now be broken.

This request is to allow multiple domains per tenant. This is particularly useful when you have an internal hostname for users on the internal network, it's not considered feasible to route requests from the internal network to the WAF so the public hostname cannot be used in that case.

Summary:

• Multiple domains per tenant regardless of those routers exposing the internal/external networks
• Tenant should be reachable via the service directly using the service name