Duplicate worker IAM role is being created

[apaterson-ecs]

When we stand up our EKS cluster using this module i have been noticing two worker IAM roles being created. I believe this to be a duplicate and not necessary as the EKS module creates the worker IAM role and attaches the policies.

This is causing a bit of confusion when we re-run our Terraform plan as it wants to remove one of the worker IAM roles from the aws_iam_policy_attachment resources. We don't want to see this in our Terraform plan every time we run it.

File references as follows:
https://github.com/terraform-aws-modules/terraform-aws-eks/blob/master/workers.tf#L402
https://github.com/spotinst/terraform-spotinst-ocean-eks/blob/master/eks.tf#L22

Is there a particular reason as to why you included the aws_iam resources in your module even though it is in the Terraform EKS module?