With 6e77da640aa84c1efe330d4a5224c9c7425ece57, the documentviewer
demo's TxtViewer plugin has been fully documented in order to replace
the Application example.
This patch moves the application example to manual tests.
Pick-to: 6.5
Change-Id: I67d975e478c7bc840613c8af1301a4eafe8f1a42
Reviewed-by: Qt CI Bot <qt_ci_bot@qt-project.org>
Reviewed-by: Volker Hilsheimer <volker.hilsheimer@qt.io>
