Retain WS_MAXIMZE when unminmizing a maximized window (#2581)

Co-authored-by: Markus Siglreithmaier <m.siglreith@gmail.com>

examples/window_debug.rs

@@ -51,6 +51,7 @@ fn main() {
                     if minimized {
                         minimized = !minimized;
                         window.set_minimized(minimized);
+                        window.focus_window();
                     }
                 }
                 VirtualKeyCode::V => {