NOTIFICATION_WM_CLOSE_REQUEST is incorrectly described to exist in MainLoop by some documentation.

**Your Godot version:** v4.2.stable.official

**Issue description:**
`MainLoop.NOTIFICATION_WM_QUIT_REQUEST` and `MainLoop.NOTIFICATION_WM_CLOSE_REQUEST` are referenced, but neither one works (despite the phrasing "you _can_ remove the MainLoop. prefix" implying that it is optional); the only one that works is `NOTIFICATION_WM_CLOSE_REQUEST`.

`MainLoop` class documentation correctly _excludes_ both but does not direct the user to the correct location of these constants; maybe they were removed from the class unintentionally?

**URL to the documentation page:**
https://docs.godotengine.org/en/stable/tutorials/migrating/upgrading_to_godot_4.html
> MainLoop's NOTIFICATION_ constants were duplicated to Node which means you can remove the MainLoop. prefix when referencing them.
> MainLoop's NOTIFICATION_WM_QUIT_REQUEST is now NOTIFICATION_WM_CLOSE_REQUEST.

https://docs.godotengine.org/en/stable/classes/class_mainloop.html