tst_QItemDelegate::dateTimeEditor() remove setActiveWindow()

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

Remove 2 redundant calls.

Task-number: QTBUG-121488
Change-Id: I8f8d6e5988759836a880c6c141605f0593f81098
Reviewed-by: Axel Spoerl <axel.spoerl@qt.io>

tests/auto/widgets/itemviews/qitemdelegate/tst_qitemdelegate.cpp

@@ -747,7 +747,6 @@ void tst_QItemDelegate::dateTimeEditor()
     widget.setItem(0, 2, item3);
     widget.show();
     QVERIFY(QTest::qWaitForWindowExposed(&widget));
-    QApplicationPrivate::setActiveWindow(&widget);
 
     widget.editItem(item1);
 
@@ -763,7 +762,6 @@ void tst_QItemDelegate::dateTimeEditor()
     timeEditor->setTime(time.addSecs(60));
 
     widget.clearFocus();
-    QApplicationPrivate::setActiveWindow(&widget);
     widget.setFocus();
     widget.editItem(item2);