curl --request GET \
  --url https://www.postable.com/api/v1/groups/{groupId} \
  --header 'Authorization: Bearer <token>'

{
  "id": 123,
  "name": "<string>",
  "description": "<string>",
  "created_at": "2023-11-07T05:31:56Z",
  "updated_at": "2023-11-07T05:31:56Z"
}