[BACKPORT] apply fix to invalid reference to trac #4440

Author: timlinux

src/app/qgisapp.cpp

@@ -6471,7 +6471,7 @@ void QgisApp::oldProjectVersionWarning( QString oldVersion )
                               "<p>Version of the project file: %1<br>Current version of QGIS: %2" )
                           .arg( oldVersion )
                           .arg( QGis::QGIS_VERSION )
-                          .arg( "<a href=\"https://trac.osgeo.org/qgis\">http://trac.osgeo.org/qgis</a> " )
+                          .arg( "<a href=\"http://hub.qgis.org/projects/quantum-gis\">http://hub.qgis.org/projects/quantum-gis</a> " )
                           .arg( tr( "<tt>Settings:Options:General</tt>", "Menu path to setting options" ) )
                           .arg( tr( "Warn me when opening a project file saved with an older version of QGIS" ) )
                         );