add aws eks update-kubeconfig

[45cali]

Currently the helm step only takes advantage of kube context that has already been configured.
Can you add an option for this step to run this prior to running helm upgrade?

aws eks --region <region> update-kubeconfig --name <cluster name> --alias <friendly name>

[45cali]

or can you at least add aws-cli so in our kubeconfig this runs

- name: arn:aws:eks:<region>:<account>:cluster/<cluster>
  user:
    exec:
      apiVersion: client.authentication.k8s.io/<vesion>
      args:
      - --region
      - <region>
      - eks
      - get-token
      - --cluster-name
      - <cluster>
      command: aws
      env:
      - name: AWS_PROFILE
        value: <profile>
        ```

[45cali]

#446 can this get reviewed please.

[kostis-codefresh]

You should be able to run a step with aws-cli just before the Helm step.

  ChangeContext:
    title: Change K8s context
    image: 'amazon/aws-cli:2.11.23'
    commands:
      - aws eks --region <region> update-kubeconfig --name <cluster name> --alias <friendly name>
   YourHelmStep:
    [....]