v1.1.0: Workflow: Add documentation in gh-pages (#126)

* Update CI nim version

* Add guzba's recommended workflow to generate documentation on gh-pages

* Reupdate the Nim CI version

---------

Co-authored-by: Dimitri LESNOFF <dimitri.lesnoff@lip6.fr>
Co-authored-by: Miran <narimiran@disroot.org>