We already have the string representation QFETCH()ed, so let's use it.
This also seems to test op<<, by QCOMPARE() falling back to
QDebug::toString().
Change-Id: Ibec66d4b7301e71509497a06b1b65e5cf9d108c2
Reviewed-by: Ivan Solovev <ivan.solovev@qt.io>
(cherry picked from commit 9122bfcc4d)
Reviewed-by: Qt Cherry-pick Bot <cherrypick_bot@qt-project.org>