Update autoscaling use-case in user demo

[viktor-f]

Is your feature request related to a problem? Please describe.
The user demo currently includes a horizontal pod autoscaler. But we would like to extend the autoscaling use case to be a bit more useful.

Describe the solution you'd like
Implement an endpoint in the user demo that drastically increases the cpu usage for one of the pods. This should in turn trigger the pod autoscaling and create a new pod. Make sure that this function is properly bound so that the pod autoscaler does not continue creating more pods forever. This would also allow us to showcase cluster autoscaling in clusters where that is available.

Describe alternatives you've considered

Additional context