Updated dead link to Madeleine.js source (#20322)

Author: BurritoVoid

docs/content/doc/advanced/customizing-gitea.en-us.md

@@ -202,7 +202,7 @@ You can display STL file directly in Gitea by adding:
 
 to the file `templates/custom/footer.tmpl`
 
-You also need to download the content of the library [Madeleine.js](https://jinjunho.github.io/Madeleine.js/) and place it under `$GITEA_CUSTOM/public/` folder.
+You also need to download the content of the library [Madeleine.js](https://github.com/beige90/Madeleine.js) and place it under `$GITEA_CUSTOM/public/` folder.
 
 You should end-up with a folder structure similar to: