curl --request POST \
  --url https://sandbox.cucu.bo/api/v1/api/v1/invoice/config/digitalSign \
  --header 'Content-Type: multipart/form-data' \
  --header 'cucukey: <cucukey>' \
  --form privateKey='@example-file' \
  --form cert='@example-file'

{
  "message": "COMPLETED",
  "errors": null,
  "success": true,
  "data": {
    "privateKey": "YES",
    "cert": "YES"
  }
}