List family instance types

curl --request GET \
  --url https://cloud-api.phala.com/api/v1/instance-types/{family}

{
  "items": [
    {
      "id": "<string>",
      "name": "<string>",
      "description": "<string>",
      "vcpu": 123,
      "memory_mb": 123,
      "hourly_rate": "<string>",
      "requires_gpu": true,
      "default_disk_size_gb": 20,
      "family": "<string>"
    }
  ],
  "total": 123,
  "family": "<string>"
}