If QtQuickTest executable is given a non-matching test function name, it still exits successfully

If QtQuickTest test executable was given filters that didn't match in any of the
qml files run, it exited successfully.

In combination with a Coin bug when the test function name contains a space,
this allowed failing tests to pass the CI. If the test function fails, the
repeat attempts would pass two arguments to the executable. Neither of those
hit, but that wasn't considered a problem.