The class is not intended for inheriting from it (see also
e502906305), so we can mark it as final
to explicitly forbid this. The tests were still using it as a base
class to clean the results during destruction, so fix them accordingly.
Task-number: QTBUG-99883
Pick-to: 6.3
Change-Id: I4a7ee3e2b462bd704e4b5a95ed733144805d6e5b
Reviewed-by: Mårten Nordheim <marten.nordheim@qt.io>
Reviewed-by: Marc Mutz <marc.mutz@qt.io>
d1639da0d5