CollectionSubFolder

{
    "id": "FID001",
    "type": "CollectionSubFolder",
    "attributes": {
        "type": "sub-folder",
        "name": "string"
    },
    "relationships": {
        "collection": {
            "data": {
                "id": "FID001",
                "type": "Collection"
            }
        },
        "coverImage": {
            "data": {
                "id": "FID001",
                "type": "File"
            }
        },
        "items": {
            "data": [
                {
                    "id": "FID001",
                    "type": "CollectionItem"
                }
            ]
        }
    }
}