text: Title: HPA on GKE uses aggregated node CPU utilisation and not pods in targeted deployment
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  **What happened**:
  HPA is scaling with respect to overall CPU utilisation of the node
  
  **What you expected to happen**:
  HPA should autoscale only with respect to CPU utilisation of the pods from the target deployment
  
  **How to reproduce it (as minimally and precisely as possible)**:
  Following the example here https://cloud.google.com/kubernetes-engine/docs/how-to/horizontal-pod-autoscaling,
  
  and many other test as explained in my query here https://stackoverflow.com/questions/60872188/gke-hpa-only-targeting-node-cpu-utilisation-rather-than-targeted-deployments/60876287?noredirect=1#comment107727882_60876287
  
  It appears that for deployments with a hpa defined as below the metrics used are global CPU usage and not deployment or pod cpu usage.
  
  ```
  apiVersion: autoscaling/v2beta1
  kind: HorizontalPodAutoscaler
  metadata:
    name: nginx
  spec:
    maxReplicas: 10
    minReplicas: 1
    scaleTargetRef:
      apiVersion: apps/v1
      kind: Deployment
      name: nginx
    metrics:
    - type: Resource
      resource:
        name: cpu
        targetAverageUtilization: 50```
  
  **Anything else we need to know?**:
  
  **Environment**:
  - Kubernetes version: v1.14.10-gke.27
  - Cloud provider or hardware configuration: GKE
  