Notebook delta-lake-python.ipynb is broken in main

[N-o-Z]

Error:

OSError: Generic S3 error: response error "request error", after 0 retries: builder error for url (http://lakefs:8000/delta-lake-demo/main/userdata/_delta_log/_last_checkpoint): URL scheme is not allowed

[N-o-Z]

Possibly also modify the check-notebooks workflow to run periodically on main?

[kesarwam]

Fixed this notebook: https://github.com/treeverse/lakeFS-samples/pull/146