Fix shortcuts when using setDefaultAction

Don't remove ampersands when setting the text: they will be removed when
the text is displayed. This fixes double removal of ampersands.

[ChangeLog][QtWidgets][QToolButton] Fix double removal of ampersands

Task-number: QTBUG-23396
Change-Id: I56bf50eb24aae32a81d614824aca0b63363587c8
Reviewed-by: Timur Pocheptsov <Timur.Pocheptsov@digia.com>

src/widgets/widgets/qtoolbutton.cpp

@@ -897,7 +897,7 @@ void QToolButton::setDefaultAction(QAction *action)
         return;
     if (!actions().contains(action))
         addAction(action);
-    setText(action->iconText());
+    setText(action->text());
     setIcon(action->icon());
 #ifndef QT_NO_TOOLTIP
     setToolTip(action->toolTip());