Retrieves an alert field

curl --request GET \
  --url https://api.rootly.com/v1/alert_fields/{id} \
  --header 'Authorization: Bearer <token>'

{
  "data": {
    "type": "alert_fields",
    "attributes": {
      "slug": "<string>",
      "name": "<string>",
      "kind": "<string>",
      "created_at": "<string>",
      "updated_at": "<string>"
    },
    "id": "<string>"
  }
}