fix deprecated warning QButtonGroup::buttonClicked

This function is obsolete.

Use QButtonGroup::idClicked instead.
This function was introduced in Qt 5.15.

sources/qetgraphicsitem/ViewItem/ui/graphicstablepropertieseditor.h

@@ -20,6 +20,7 @@
 
 #include "PropertiesEditor/propertieseditorwidget.h"
 #include <QPointer>
+#include <QButtonGroup>
 
 namespace Ui {
 class GraphicsTablePropertiesEditor;