/broadcasts/{id}/cancel
curl -X POST "https://example.com/broadcasts/497f6eca-6276-4993-bfeb-53cbbbba6f08/cancel"{ "object": "broadcast", "id": "497f6eca-6276-4993-bfeb-53cbbbba6f08", "canceled_remaining": 0}curl -X POST "https://example.com/broadcasts/497f6eca-6276-4993-bfeb-53cbbbba6f08/cancel"{ "object": "broadcast", "id": "497f6eca-6276-4993-bfeb-53cbbbba6f08", "canceled_remaining": 0}