### Godot version

Godot Engine v4.0.stable.official.92bee43ad

### System information

Windows 10

### Issue description

The documentation states that passing ```null``` into the image parameter of ```set_custom_mouse_cursor``` will change it back to the system cursor, however I find that it removes the cursor's image entirely, rather than setting it to the system's cursor.


### Steps to reproduce

```var isimage = false
var theimage = load("res://final.png")

func _on_my_button_pressed():
    if isimage == false:
        Input.set_custom_mouse_cursor(theimage, Input.CURSOR_ARROW, Vector2(16,16))
        isimage = true
        
    else:
        Input.set_custom_mouse_cursor(null)
        isimage = false```

When the button is pressed, the cursor is meant to change to the new cursor. When it has been pressed a second time, it changes back to the default cursor. However, upon pressing it a second time, it simply disappears. The cursor becomes visible again when the cursor exits and re-enters the window.

### Minimal reproduction project

[null mouse.zip](https://github.com/godotengine/godot/files/10901969/null.mouse.zip)

register_create_function("windows", create_func, get_rendering_drivers_func);
}
DisplayServerWindows::~DisplayServerWindows() {
	delete joypad;
	touch_state.clear();
	cursors_cache.clear();
	if (mouse_monitor) {
		UnhookWindowsHookEx(mouse_monitor);
	}
	if (user_proc) {
		SetWindowLongPtr(windows[MAIN_WINDOW_ID].hWnd, GWLP_WNDPROC, (LONG_PTR)user_proc);
	}
	
	screen_set_keep_on(false);
#ifdef GLES3_ENABLED
	
	
#endif
	if (windows.has(MAIN_WINDOW_ID)) {
#ifdef VULKAN_ENABLED
		if (context_vulkan) {
			context_vulkan->window_destroy(MAIN_WINDOW_ID);
		}
#endif
		if (wintab_available && windows[MAIN_WINDOW_ID].wtctx) {