[26.0] Fix AttributeError when dataset in inheritance chain has no user

[mvdbeek]

How to test the changes?

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• I've included appropriate automated tests.
• This is a refactoring of components with existing test coverage.
• Instructions for manual testing are as follows:
  1. [add testing steps and prerequisites here if you didn't write automated tests covering all your changes]

License

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[github-actions]

This PR was merged without a "kind/" label, please correct.