Return a Promotion

curl --request GET \
  --url http://{defaultHost}/api/v2/platform/promotions/{id} \
  --header 'Authorization: Bearer <token>'

{
  "data": {
    "id": "44",
    "type": "promotion",
    "attributes": {
      "description": null,
      "expires_at": null,
      "starts_at": null,
      "name": "Promo",
      "type": null,
      "usage_limit": null,
      "match_policy": "all",
      "code": null,
      "advertise": false,
      "path": null,
      "created_at": "2022-11-08T19:35:03.971Z",
      "updated_at": "2022-11-08T19:35:03.973Z",
      "public_metadata": {},
      "private_metadata": {}
    },
    "relationships": {
      "promotion_category": {
        "data": {
          "id": "17",
          "type": "promotion_category"
        }
      },
      "promotion_rules": {
        "data": [
          {
            "id": "16",
            "type": "promotion_rule"
          }
        ]
      },
      "promotion_actions": {
        "data": [
          {
            "id": "31",
            "type": "promotion_action"
          }
        ]
      },
      "stores": {
        "data": [
          {
            "id": "387",
            "type": "store"
          }
        ]
      }
    }
  }
}