fix link to dev documentation

Signed-off-by: Arthur Schiwon <blizzz@arthur-schiwon.de>

.github/CONTRIBUTING.md

@@ -58,7 +58,7 @@ like `git config --global alias.ci 'commit -s'`. Now you can commit with
 
 In case you are not sure how to add or update the license header correctly please have a look at [contribute/HowToApplyALicense.md][applyalicense]
 
-[devmanual]: https://docs.nextcloud.org/server/13/developer_manual/
+[devmanual]: https://docs.nextcloud.com/server/latest/developer_manual/
 [dcofile]: https://github.com/nextcloud/server/blob/master/contribute/developer-certificate-of-origin
 [applyalicense]: https://github.com/nextcloud/server/blob/master/contribute/HowToApplyALicense.md