curl --request POST \
  --url http://localhost:8080/v1/batches/{batch_id}/cancel \
  --header 'x-model-provider: <x-model-provider>'

{
  "id": "<string>",
  "object": "<string>",
  "status": "<string>",
  "cancelling_at": 123,
  "cancelled_at": 123,
  "extra_fields": "<unknown>"
}