Feature Change - Service Resources - Make auto-scale parameters of App Gateway configurable

The default min and max instances for App Gateway are 2 and 10 respectively.

For environments that take high volume of loads, these configurations are not sufficient.

Provide a way to give inputs for min and max instances for App Gateway so that they can be configured as needed.

More details

Observed 5xx during performance testing.

Which was caused by a dip in health probes of all the services.

The issue is root caused to App Gateway not having enough instances to be able to handle the load.

Making auto-scale params configurable, gives the environment owners the flexibility to adjust auto scaling parameters as required.