Fix docs link

Author: colinodell

docs/2.2/extensions/autolinks.md

@@ -47,7 +47,7 @@ echo $converter->convert('I successfully installed the https://github.com/thephp
 
 ## `@mention`-style Autolinking
 
-As of v1.5, [mention autolinking is now handled by a Mention Parser outside of this extension](/2.2/extensions/mention/).
+As of v1.5, [mention autolinking is now handled by a Mention Parser outside of this extension](/2.2/extensions/mentions/).
 
 [link-league-commonmark]: https://github.com/thephpleague/commonmark
 [link-gfm-spec-autolinking]: https://github.github.com/gfm/#autolinks-extension-