List webhook endpoints

Example response

{
  "data": [
    {
      "id": "ep_1srOrx2ZWZBpBUvZwXKQmoEYga2",
      "description": "Production webhook endpoint",
      "url": "https://example.com/webhook",
      "event_types": [
        "customer.created",
        "customer.updated"
      ],
      "created_at": "2024-01-20T16:04:11Z"
    }
  ]
}