[Docs] Update/Message Board Tutorial

[MaxxReis]

I worked on revising the tutorial, ensuring a more accurate understanding of the content and checking the steps needed to successfully complete the tutorial.

1. Added section for using auth0 authentication
2. Added note for tutorial introduction
3. Corrections in code snippets
4. Inclusion of codes to complete the tutoria
5. Text tweaks to improve overall understanding

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[github-actions[bot]]

This PR has been stale for 60 days and will be closed automatically in 7 days. Comment to keep it open.

[rderbier]

Doc parts have been updated already. Closing the PR.

[rderbier]

doc up-to-date. Messageboard specifics to be re-tested on v24.