use qtconcurrent instead of qtgui in test code

this works with -no-gui, and doesn't interfere with our upcoming ANGLE
hackery.

Change-Id: I2985cc0acd1fbf185b8967ffe58606b1b7dd9d1e
Reviewed-by: Friedemann Kleint <Friedemann.Kleint@digia.com>
Reviewed-by: Olivier Goffart <ogoffart@woboq.com>

tests/auto/tools/moc/no-keywords.h

@@ -47,7 +47,7 @@
 #define slots Baz
 #define emit Yoyodyne
 
-#include <QtGui/QtGui>
+#include <QtConcurrent/QtConcurrent>
 #include <QtCore>
 #include <QtNetwork/QtNetwork>
 #include <QtSql/QtSql>