curl --request GET \
  --url https://api.cal.com/v2/calendars/busy-times \
  --header 'Authorization: <authorization>'

{
  "status": "success",
  "data": [
    {
      "start": "2023-11-07T05:31:56Z",
      "end": "2023-11-07T05:31:56Z",
      "source": "<string>"
    }
  ]
}