Retrieves a heartbeat

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

{
  "data": {
    "id": "7a7b6317-e3bd-4ead-8ae7-9743471473d8",
    "type": "heartbeats",
    "attributes": {
      "slug": "omnis-dignissimos-eaque-et",
      "name": "Omnis dignissimos eaque et.",
      "description": "Porro reiciendis et aliquid.",
      "alert_summary": "API is down",
      "alert_description": null,
      "alert_urgency_id": "9cef380c-b507-4364-b69f-dfc001a83c0d",
      "interval": 5,
      "interval_unit": "seconds",
      "notification_target_id": "212",
      "notification_target_type": "User",
      "ping_url": "http://localhost:3001/v1/heartbeats/7a7b6317-e3bd-4ead-8ae7-9743471473d8/ping",
      "secret": "heartbeat_adb770ce8ceda46c5ac8b835d2373168607f267bd1fd41785b9f0a912f1eaee7",
      "email_address": "heartbeat-07c3cc500f4ad81381e882c6025b808a@test.email.rootly.com",
      "last_pinged_at": null,
      "expires_at": null,
      "enabled": false,
      "status": "waiting",
      "updated_at": "2025-11-14T13:14:00.934-08:00",
      "created_at": "2025-11-14T13:14:00.934-08:00"
    }
  }
}