The Application Auto Scaling service automatically attempts to manage IAM Service-Linked Roles when registering certain service namespaces for the first time. To manually manage this role, see the aws_iam_service_linked_role resource.
とのこと。でもサービスリンクロール、マネージドポリシーみたいに最初っから作ってくれてたらいいのにね
https://registry.terraform.io/providers/hashicorp/aws/latest/docs/resources/appautoscaling_target
