Running the EKS CoreDNS deployment on Fargate when using the Terraform EKS module

edit-coredns.tf

# By default, the AWS EKS API creates the coredns deployment template with an annotation
# `eks.amazonaws.com/compute-type` equal to `ec2`. This prevents coredns pods from running on Fargate.
# Removing this annotation fixes the issue.
# More on: https://github.com/hashicorp/terraform-provider-aws/issues/11327
resource "null_resource" "edit_coredns" {
  provisioner "local-exec" {
    environment = {
      KUBECONFIG   = module.eks.kubeconfig_filename
      CLUSTER_NAME = local.cluster_name
    }
    command = <<EOF
      sleep 60
      aws eks update-kubeconfig --name $CLUSTER_NAME
      kubectl -n kube-system patch deployment coredns \
        --type json -p='[
          {"op": "add", "path": "/spec/template/metadata/annotations", "value": {}},
          {"op": "add", "path": "/spec/template/metadata/annotations/eks.amazonaws.com~1compute-type", "value": "to-be-removed"}
          ]'

      kubectl -n kube-system patch deployment coredns \
        --type json -p='[{"op": "remove", "path": "/spec/template/metadata/annotations/eks.amazonaws.com~1compute-type"}]'

      kubectl -n kube-system rollout restart deployment coredns
      kubectl -n kube-system rollout status deployment coredns

      EOF
  }
}