Use a precise timer in tst_QTimer::remainingTime

At 200 ms, the error on first firing could be 10 ms.

Task-number: QTBUG-58519
Change-Id: Ifaee7464122d402991b6fffd14a02a4ce782f11f
Reviewed-by: Allan Sandfeld Jensen <allan.jensen@qt.io>

tests/auto/corelib/kernel/qtimer/tst_qtimer.cpp

@@ -158,6 +158,7 @@ void tst_QTimer::remainingTime()
     QTimer timer;
 
     connect(&timer, SIGNAL(timeout()), &helper, SLOT(timeout()));
+    timer.setTimerType(Qt::PreciseTimer);
     timer.start(200);
 
     QCOMPARE(helper.count, 0);