Make sure multiple_outputs is inferred correctly even when using TypedDict

[noamcohen97]

According to the documentation here, the multiple_outputs parameter should automatically set to true if a dict is being used as the function return type.
The current condition in _infer_multiple_outputs() does not consider a TypedDict as a dict for that matter, as well as any other subclass of dict.
This PR uses issubclass() to make sure any typing.Mapping subclass will make multiple_outputs=True

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[boring-cyborg]

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[jscheffl]

Now just a small "glitch" in imports due to static checks... https://github.com/apache/airflow/actions/runs/7444185558/job/20275885423?pr=36652

[josh-fell]

Probably worth adding a note about this to the doc you referenced too.

[eladkal]

LGTM

[boring-cyborg]

Awesome work, congrats on your first merged pull request! You are invited to check our Issue Tracker for additional contributions.