Typedoc complains about the links from the reference to the cover.md.
I couldn't find a way to make those warnings go away, but the links work.
As a remedy, `treatWarningsAsErrors` is removed temporarily.
Similarly, the relative links aren't supported either, so link to the latest
Slint docs.
Fixes#6488
ChangeLog: Added function to set the XDG app id on Wayland/X11. This needs to be added with respective function names in the language sections.
Fixes#1332
