The test above this one loads hello.txt, but we don't wait for the "load
finished" message, so it can arrive after the previous test already finished and
make this test not wait properly.
However, we also can't easily wait for the load finished message in the
previous test as it only appears with QtWebEngine, not QtWebKit.
As a workaround, we simply load another file in that test, to circumvent this
kind of cross-interaction.