docs: public void setProperties( Map<String,String> properties ) {
          Map<String,String> userProperties = systemSession.getUserProperties();
          if ( userProperties == null ) {
              userProperties = new HashMap<String,String>();
          }
          userProperties.putAll( properties );
          
          log.debug( "Session userProperties: {}", userProperties );
          
          systemSession = (MavenRepositorySystemSession)systemSession.setUserProperties( userProperties );
          
      }