CAO 2.2 Cluster Autoscaling - Concept page or Tutorial explaining how to set the downscale

As per PRD - In CAO 2.2, we have to disable the default downscaling operation. The Downscaling should only occur with User-Defined Thresholds.

And so, we also need to explain Downscale - behavior with an example along with the Upscale on Cluster-Autoscaling concept page or in Tutorial whichever is feasible.

This is both an improvement and a doc page change. We discussed this couple of times, but still, some confusion remained. Hence, creating a separate ticket - This is 'a MUST NOW - P0' for 2.2 Autoscaling.