Configmap -auth-config for Guest Clusters does not persist changes when authenticator pod restarts

Guest Clusters use ${CLUSTER_NAME}-auth-config for the AWS IAM Authenticator for the Guest Cluster. If the authenticator pod restarts after editing the configmap, the configmap reverts back to the spec as defined [here](https://github.com/awslabs/kubernetes-iteration-toolkit/blob/main/operator/pkg/components/iamauthenticator/iamauthenticator.go#L140-L161).

I'm unsure if permissions persist to the guest cluster without restarting the authenticator pod.

Start with operator/pkg/components/iamauthenticator/iamauthenticator.go at lines 140-161, then trace how the Guest Cluster auth ConfigMap is reconciled and reproduce an authenticator pod restart after editing it. Check whether permissions persist without a restart; done means the edited ConfigMap and its permissions remain consistent after the pod restarts.

Written by the indexing model from the issue text.