mkdocs.yml + user_doc_4_6

Fix some not-down-ported cases

Author: adriendupuis

mkdocs.yml

@@ -705,6 +705,7 @@ extra:
 
   symfony_doc: 'https://symfony.com/doc/5.x'
   user_doc: 'https://doc.ibexa.co/projects/userguide/en/3.3'
+  user_doc_4_6: 'https://doc.ibexa.co/projects/userguide/en/4.6'
 
 extra_css:
   - fonts/MavenPro.css