wip: excel multisheet dataset

[GabrielAzevedoFerreiraQB]

Description

It is a wip for now and I wanted to see if there is interest in this.

It seems a bit too obvious not to be there already, so I wonder if there is any reason (except no one added)

Development notes

Checklist

• Read the contributing guidelines
• Opened this PR as a 'Draft Pull Request' if it is work-in-progress
• Updated the documentation to reflect the code changes
• Added a description of this change and added my name to the list of supporting contributions in the RELEASE.md file
• Added tests to cover my changes

Notice

• I acknowledge and agree that, by checking this box and clicking "Submit Pull Request":

• I submit this contribution under the Apache 2.0 license and represent that I am entitled to do so on behalf of myself, my employer, or relevant third parties, as applicable.

• I certify that (a) this contribution is my original creation and / or (b) to the extent it is not my original creation, I am authorised to submit this contribution on behalf of the original creator(s) or their licensees.

• I certify that the use of this contribution as authorised by the Apache 2.0 license does not violate the intellectual property rights of anyone else.

[datajoely]

Closing in favour of #963 - thank you for pushing things forward @GabrielAzevedoFerreiraQB !