Fix macro definition mistake

Sine Striker

2023-12-10 db00428f146a7daf2c8b5c4de6c8c1e317f950a4

 examples/mainwindow/mainwindow.cpp

@@ -99,5 +99,6 @@
    setMenuWidget(windowBar);
    setCentralWidget(clockWidget);
    setWindowTitle("Example MainWindow");
    // setContentsMargins({0, 1, 0, 0});
    resize(640, 480);
}