Posture check: AWS ECS cluster not configured with a registered instance
Query: ```config from cloud.resource where api.name = 'aws-ecs-service' AND json.rule = launchType equals EC2 as X; config from cloud.resource where api.name = 'aws-ecs-cluster' AND json.rule = status equals ACTIVE and registeredContainerInstancesCount equals 0 as Y; filter '$.X.clusterArn equals $.Y.clusterArn'; show Y;```