Create new page for autoscaling

[viktor-f]

Is your feature request related to a problem? Please describe.
We currently have a page for cluster api that has some information about autoscaling. We want to extract this information to a separate page and add more information to it.

Describe the solution you'd like
Create a new page for autoscaling, it should be in "For app devs"/"go deeper" after CI/CD.

The page should cover information about both pod autoscaling and cluster autoscaling, including how they can work together. The information about cluster autoscaling on this page can be used as a start for that part. It must also cover welkin specifics such as,

• How can a reader determine if cluster autoscaling is available in welkin
  • Including how to check available node groups, sizes, and limits
• How they can request new autoscaling node groups
  • Including recommendation to add taints to ensure only workload intended for such nodes get scheduled, especially for large or specialised nodes.
• How can pod autoscaling be used in welkin
• A running example of user-demo, showing the commands used to trigger an increased load, launching a new pod and a new node.

Definition of done
There is now documentation for autoscaling in the navbar after CI/CD