Replace ref to docusaurus with Sphinx

CHANGELOG.md

@@ -40,6 +40,10 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/).
 
 - Add examples for building overlays in parallel to documentation
 
+### Changed
+
+- Replace reference to docusaurus with Sphinx
+
 ## v4.5.2, 2024-05-13
 
 ### Added

userdocs/contributing/documentation.rst

@@ -13,8 +13,8 @@ suggest an improvement
 `pull request <https://github.com/warewulf/warewulf-web/compare>`_ on
 `our repository <https://github.com/warewulf/warewulf-web>`_.
 
-The current documentation is generated with `Docusaurus
-<https://v2.docusaurus.io/docs/>`_.
+The current documentation is generated with `Sphinx
+<https://www.sphinx-doc.org/>`_.
 
 For more information on using Git and GitHub to create a pull request
 suggesting additions and edits to the docs, see the `section on