Get the categories of the category group

{
  "has_more": true,
  "next_cursor": "<string>",
  "items": [
    {
      "id": 123,
      "label": "<string>",
      "direction": "cash_in",
      "created_at": "<string>",
      "updated_at": "<string>",
      "category_group": {
        "id": 123,
        "url": "<string>"
      }
    }
  ]
}