A new URL for oeo-extended

[adelmemariani]

Description of the issue

There is a new repository for oeo-extended. This should be visible on the ontology page.

Workflow checklist

• [ ] I am aware of the workflow in CONTRIBUTING.md

[jh-RLI]

Before we do this, we need to import the oeo and oeo extended into the oekb. Then we have a "single source" where we can retrieve the oeo + extended data. Referencing the diagram that we drew during the project meeting.