[Feature] Enable "cluster-autoscaler-profile enable-proactive-scaleup" feature for Cluster Autoscaler

[KK291860]

Is your feature request related to a problem? Please describe.
We are fine tuning the cluster autoscaler and found that AKS is not supporting the parameter 'enable-proactive-scaleup'.
This parameter would help our environment to scale proactively based on the upcoming scaling requirements.

Describe the solution you'd like
az aks update --resource-group sep-eus1-devqa-aks-rg --name sep-eus1-devqa-test-aks02 --subscription 'Sephora Lower Environment' --cluster-autoscaler-profile enable-proactive-scaleup=true

We should be able to enable/disable this parameter like above

[microsoft-github-policy-service]

Action required from @aritraghosh, @julia-yin, @AllenWen-at-Azure