Doc: clarify trigger rule behavior for removed upstream state

[nailo2c]

Hi team, I found a few places that docs description are not aligned with the code.

For example, all_done_setup_success is one of the trigger rules (code link) but it is not in the docs.

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[jason810496]

Would it be a good idea to introduce docs level prek hooks to make sure all the task states are defined in airflow-core/docs/core-concepts/dags.rst?