QmlDesigner: Fix qbs build and building with Qt6.2

Change-Id: Ic114c9eb830eed5cf0bef890007408694453791e
Reviewed-by: Christian Kandeler <christian.kandeler@qt.io>

src/plugins/qmlprojectmanager/buildsystem/qmlbuildsystem.cpp

@@ -37,6 +37,8 @@
 
 #include "texteditor/textdocument.h"
 
+#include <QAction>
+
 using namespace ProjectExplorer;
 namespace QmlProjectManager {