docs: Add Mountpoint S3 CSI Driver to the list of optional supported …

…policies for IRSA role (#533)

modules/iam-role-for-service-accounts-eks/README.md

@@ -15,6 +15,7 @@ Creates an IAM role which can be assumed by AWS EKS `ServiceAccount`s with optio
 - [App Mesh Controller](https://github.com/aws/aws-app-mesh-controller-for-k8s/blob/master/config/iam/controller-iam-policy.json)
   - [App Mesh Envoy Proxy](https://raw.githubusercontent.com/aws/aws-app-mesh-controller-for-k8s/master/config/iam/envoy-iam-policy.json)
 - [Managed Service for Prometheus](https://docs.aws.amazon.com/prometheus/latest/userguide/set-up-irsa.html)
+- [Mountpoint S3 CSI Driver](https://github.com/awslabs/mountpoint-s3/blob/main/doc/CONFIGURATION.md#iam-permissions)
 - [Node Termination Handler](https://github.com/aws/aws-node-termination-handler#5-create-an-iam-role-for-the-pods)
 - [Velero](https://github.com/vmware-tanzu/velero-plugin-for-aws#option-1-set-permissions-with-an-iam-user)
 - [VPC CNI](https://docs.aws.amazon.com/eks/latest/userguide/cni-iam-role.html)