I've been on the hunt for a Terraform module that edits the aws-auth configmap (from EKS) when creating a cluster. I came across a few solutions, some workarounds, and others that made the whole cluster with the changed configmap. But, what I needed was a separate module to run after the main EKS creation resource.
It might be handy for your projects (automating roles is always a good idea):
• Repository link: https://github.com/cayohollanda/terraform-aws-eks-auth
• Terraform registry link: https://registry.terraform.io/modules/cayohollanda/eks-auth/aws/latest?tab=inputs
If it helps you out, please give it a star. If you have any questions, just drop me a message on Slack and I'll get back to you as soon as I can.