docs: Update link to Open WebUI docs (#2549)

Fix dead link to Open WebUI docs

Signed-off-by: Welteam <[email protected]>

Author: Welteam

docs/integrations/openwebui.md

@@ -4,4 +4,4 @@ Docling is available as a plugin for [Open WebUI](https://github.com/open-webui/
 - 💻 [GitHub][github]
 
 [github]: https://github.com/open-webui/open-webui
-[docs]: https://docs.openwebui.com/features/document-extraction/docling
+[docs]: https://docs.openwebui.com/features/rag/document-extraction/docling