curl --request GET \
  --url https://api.openregisters.com/v2/documents/{document_id}/download-url \
  --header 'X-API-Key: <api-key>'

{
  "download_url": "<string>",
  "expires_in_seconds": 123,
  "document_id": "3c90c3cc-0d44-4b50-8888-8dd25736052a",
  "kausate_id": "<string>",
  "document_sku": "<string>"
}