File _service of Package mx-service-manager

<services>
  <service name="obs_scm">
    <param name="url">https://github.com/MX-Linux/mx-service-manager.git</param>
    <param name="scm">git</param>
    <param name="revision">main</param>   
    <param name="extract">debs/*.dsc</param>
    <param name="extract">debs/*.tar.xz</param>
  </service>  
</services>