1. Proposed title of this feature request
Allow NAT Gateway as outboundType for clusters in Azure

2. What is the nature and description of the request?
Provide the ability to the Openshift IPI installer to deploy the cluster with a NAT Gateway for outbound traffic as the AKS installer already has.

For now, it needs to be achieved as a day-2 operation.

Link to AKS: https://learn.microsoft.com/en-us/azure/aks/nat-gateway#create-an-aks-cluster-with-a-managed-nat-gateway

3. Why does the customer need this? (List the business requirements here)
The customer is currently deploying clusters in Azure with ACM (IPI installation) and they're interested in this feature because they're facing the SNAT Port Exhaustion issue related to the configured outboundType by default.

4. List any affected packages or components.
Openshift Installer