GdkWin32: Avoid ShowOwnedPopups in gdk_win32_window_hide

ShowOwnedPopups(hwnd, FALSE) hides all windows that are owned by hwnd.

If a GtkWindow has any other GtkWindow as transient children,
the call to gtk_widget_hide() has the side effect of hiding also
its transient children.
Removing the call to ShowOwnedPopups(hwnd, FALSE) fixes this.
1 job for gdkwin32-fix-gdk-window-hide in 8 minutes and 19 seconds (queued for 32 minutes and 8 seconds)
Status Name Job ID Coverage
passed build #72724