Support Worker Services

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**Tell us about your request**
App Runner is great for quickly getting your apps running without any hassle but it seems to only support applications that serve http traffic only.

**Describe alternatives you've considered**
At first I just assumed that I would just not get auto scaling for a worker processes thus I would have to set my minimum/maximum to be the same number i.e. 4/4 and have to manually monitor when to scale it. Unfortunately this work around does not seem to work because as I found in the documentation it mentions:

> AWS App Runner monitors the number of concurrent requests sent to your application and automatically adds additional instances based on request volume. If your application receives no incoming requests, App Runner will scale the containers down to a provisioned instance, a **cpu throttled instance** ready that is ready to serve incoming requests within milliseconds.

The key here being that the actual instances will be throttled so my work around would not work as I confirmed with opening this question in re:post:

https://repost.aws/questions/QUEwbKE9jbTCyLn7OnqGhOrA/app-runner-scaling-for-background-service

Ideally the perfect solution for this is to allow autoscaling based of of memory/cpu usage for background workers.

I assume this might not be the easiest change to add, so an alternative that could possibly be easier would be a checkbox ☑ **"Prevent CPU Throttling"** in the auto scaling section would work.

Maybe to make it more intuitive to users who do not know, you have a checkbox ☑ "**Is Worker Process**" and if checked it auto checks the ☑ "**Prevent CPU Throttling**" checkbox and removes the minimum maximum setting and replaces it with a single input that you specify the number of instances you want and a warning saying something like "_auto scaling is currently not supported for worker processes_".