Add some missing entries to QTest::qExec()'s \sa line

Change-Id: I45300d5f9df519c5edb68d24232830bd0850915a
Reviewed-by: Paul Wicking <paul.wicking@qt.io>

src/testlib/qtestcase.cpp

@@ -1872,7 +1872,7 @@ static void initEnvironment()
     from the arguments in \c main(), it is likely of interest to use
     QTest::qExec(QObject *, const QStringList &) since it is Unicode safe.
 
-    \sa QTEST_MAIN()
+    \sa QTEST_MAIN(), QTEST_GUILESS_MAIN(), QTEST_APPLESS_MAIN()
 */
 
 int QTest::qExec(QObject *testObject, int argc, char **argv)