File _service of Package gammastep

<services>
  <service name="download_url">
    <param name="url">https://gitlab.com/chinstrap/gammastep/-/archive/v2.0.11/gammastep-v2.0.11.tar.gz</param>
    <param name="filename">gammastep-v2.0.11.tar.gz</param>
  </service>
</services>