fixes #8968

[cronoik]

This is the same PR as: link. I was asked to create a new one due to a merge mistake.

What does this PR do? (Text of the previous PR)

One of the 3.X releases introduced output objects that replaced the previously returned tuples. This PR updates the transformers notebook to reflect that update.

Fixes #8968

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@patrickvonplaten
@LysandreJik

[patrickvonplaten]

LGTM