feat: Adds support for extra helm chart options

[andskli]

This can be valuable for adding tolerations, nodeSelector, etc.

new Karpenter(stack, 'Karpenter', {
  cluster: cluster,
  namespace: 'kar-penter',
  helmExtraValues: {
    'foo.key': 'foo.value',
  },
});

Hence, you can add custom values per the values definition in the Karpenter helm chart.

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[andskli]

@deepu-james let me know if you feel this change would allow you to do what you ask for in #99?

[deepu-james]

Thanks, @andskli, I am not well knowledgeable on Helm, but If the taint on the node is

key=application:value=karpenter:effect=NoSchedule

Could you please provide an example of how the configuration would look like? I can't quite figure it out since the toleration is an array.

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EDIT Is this a correct sample?

new Karpenter(stack, 'Karpenter', {
  cluster: cluster,
  namespace: 'kar-penter',
  helmExtraValues: {
    tolerations: [{
      key: 'application',
      value: 'karpenter',
      effect: 'NoSchedule',
    }],
  },
});

If this is a right sample, could you please release a version?

[andskli]

@deepu-james yes, that looks about right given https://github.com/aws/karpenter/blob/5a32f9695e7a4327b6bc3b74f5b43cdbd7d17381/charts/karpenter/values.yaml#L83.