Is your feature request related to a problem? Please describe.
When creating an Application Gateway via APPGW_ENABLE_DEPLOY=true in the controller environment the autoscaling configuration is set to "manual" with a capacity of 2:

"properties": {
    [...]
    "sku": {
        "name": "WAF_v2",
        "tier": "WAF_v2",
        "capacity": 2
    },
}

It's neither possible to define another capacity nor to enable autoscaling.

Since we are completely managing our infrastructure via Gitops (Helm -> ArgoCD -> Kubernetes controllers) we'd like to be able to set the capacity/autoscaling setting via AGIC.

Describe the solution you'd like
We'd like to have a way (e.g. additional environment variable?) to define the capacity and to enable/disable the autoscaling.

Would you accept contributions if we are willing to implement this feature?