Fix: Helm values with correct key names in README

[same7ammar]

Description of issue:

I have tried the sample of app of apps yaml but looks like the values provided to helm are not correct .

    path: chart
    helm:
      release:   add-ons
      values: |
        cluster-autoscaler:
          enable: true
        metrics-server:
          enable: true

i can deploy it successfully the apps are not showing , i have checked the values.yml in https://github.com/aws-samples/eks-blueprints-add-ons/blob/main/chart/values.yaml#L88

you will see :

# Cluster Autoscaler Values
clusterAutoscaler:
  enable: false
  serviceAccountName:`

So correct values show be :

  targetRevision: HEAD
    path: chart
    helm:
      release: add-ons
      values: |
        clusterAutoscaler:
          enable: true
        metricsServer:
          enable: true