List training job checkpoints

curl --request GET \
--url https://api.baseten.co/v1/training_projects/{training_project_id}/jobs/{training_job_id}/checkpoints \
--header "Authorization: Api-Key $BASETEN_API_KEY"

{
  "training_job": {
    "id": "<string>",
    "created_at": "2023-11-07T05:31:56Z",
    "current_status": "<string>",
    "error_message": "<string>",
    "instance_type": {
      "id": "<string>",
      "name": "<string>",
      "memory_limit_mib": 123,
      "millicpu_limit": 123,
      "gpu_count": 123,
      "gpu_type": "<string>",
      "gpu_memory_limit_mib": 123
    },
    "updated_at": "2023-11-07T05:31:56Z",
    "training_project_id": "<string>",
    "training_project": {
      "id": "<string>",
      "name": "<string>"
    },
    "name": "gpt-oss-job"
  },
  "checkpoints": [
    {
      "training_job_id": "<string>",
      "checkpoint_id": "<string>",
      "created_at": "2023-11-07T05:31:56Z",
      "checkpoint_type": "<string>",
      "base_model": "<string>",
      "lora_adapter_config": {},
      "size_bytes": 123
    }
  ]
}