[Bug]: Open Notebook does not properly pricess .xlsx

Is this a reproducible bug?

• I confirm this is a reproducible bug, not a feature request, idea, question, or contribution proposal.

What did you do when it broke?

I uploaded an .xlsx file with 10 worksheets. Open Notebook could only "see" the last 3 of the sheets.

How did it break?

I expected it to be able to use all of the sheets.

Logs or Screenshots

No response

Open Notebook Version

v1-latest (Docker)

Environment

No response

Additional Context

No response

Contribution

• I am a developer and would like to work on fixing this issue (pending maintainer approval)