Retrieves an alert field

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

{
  "data": {
    "id": "5a2677cf-8033-4c41-91d7-5af888abd017",
    "type": "alert_fields",
    "attributes": {
      "slug": "alert-field-1",
      "name": "Alert Field 1",
      "kind": "custom",
      "created_at": "2026-01-03T21:24:05.898-08:00",
      "updated_at": "2026-01-03T21:24:05.898-08:00"
    }
  }
}