`swh-scanner` tests are currently failing for two reasons:
- `pytest-flask` removed the url method of its `LiveServer` class wrapped by
the `live_server` fixture (see [commit](https://github.com/pytest-dev/pytest-flask/commit/e9b8321b3e1051b163ad5342db0aa529e5f7ce9f)). So use recommended way to get an URL when using Flask,
this requires adding a dummy root endpoint to the API in order to get its base URL.
- migration to `CoreSWHID` was buggy due to missing typing information prior refactoring