QmlDesigner: Fix crash at shutdown

It is specifically PureActionInterface pointer that is getting deleted,
and it is subclassed, so its destructor needs to virtual for delete to
work properly.

Fixes: QDS-9221
Change-Id: Iba3b9d944de521d7e115b0d85f5a0f107b703fc1
Reviewed-by: Mahmoud Badri <mahmoud.badri@qt.io>

src/plugins/qmldesigner/components/componentcore/abstractaction.h

@@ -14,6 +14,7 @@ class QMLDESIGNERCOMPONENTS_EXPORT PureActionInterface
 {
 public:
     explicit PureActionInterface(QAction *action);
+    virtual ~PureActionInterface() = default;
     virtual void setSelectionContext(const SelectionContext &selectionContext) = 0;
     QAction *action();