Remove unused fwd declaration

Author: elpaso

src/gui/qgisinterface.h

@@ -52,7 +52,6 @@ class QgsMapLayerConfigWidgetFactory;
 class QgsMessageBar;
 class QgsPluginManagerInterface;
 class QgsRasterLayer;
-class QgsSnappingUtils;
 class QgsVectorLayer;
 class QgsVectorLayerTools;
 class QgsOptionsWidgetFactory;