[BUG] Quickstart stack fails to be deleted

[camba1]

Followed the Quickstart example to create a cluster. After completing the example. when trying to delete cluster with cdk destroy, the deletion of the Cloud Formation stack fails with:

argonamespacestructCF1D2958 Delete_failed. CloudFormation did not receive a response from your Custom Resource

Note that the EKS cluster appears to have been already been deleted at that point.

The stack can only be deleted at that point by retaining the failed resource.

Also, It would be good to add a 'Cleanup' section to the example so that people not very familiar with cdk can delete the stack. and cleanup their Kube config