QDomDocument doc refers to QXmlQuery which doesn't exist in Qt6

From https://doc.qt.io/qt-6.6/qdomdocument.html:

Note: The DOM tree might end up reserving a lot of memory if the XML document is big. For such documents, the QXmlStreamReader or the QXmlQuery classes might be better solutions.

The last Version of Qt that seams to come with QXmlQuery is 5.15. I didn't find a hint if it was removed, but as far as I can see it is not contained in Qt 6.6. So the documentation should not link to it.

Also the documentation should name an alternative to QXmlQuery for Qt 6.