Widgets module is no longer required. Removing it allows this test to
be run with a qtbase configured with -no-widgets, which saves
compilation time.
Change-Id: Id99d3f25cd7b227aa81e1cf1ac7b6fd5227ac4c4
Reviewed-by: Eskil Abrahamsen Blomfeldt <eskil.abrahamsen-blomfeldt@qt.io>