tst_QWidget::tabOrderWithCompoundWidgetsNoFocusPolicy remove setActiveW

2f6fe3a268 has made calls to
QApplicationPrivate::setActiveWindow() redundant.

Remove redundant calls.

Task-number: QTBUG-121488
Change-Id: Ieb516cc4fd02230c0ec6bb189da049c3741358dd
Reviewed-by: Axel Spoerl <axel.spoerl@qt.io>

tests/auto/widgets/kernel/qwidget/tst_qwidget.cpp

@@ -2687,7 +2687,6 @@ void tst_QWidget::tabOrderWithCompoundWidgetsNoFocusPolicy()
     container.show();
     container.activateWindow();
 
-    QApplicationPrivate::setActiveWindow(&container);
     if (!QTest::qWaitForWindowActive(&container))
         QSKIP("Window failed to activate, skipping test");