### What do you see as an issue?

The documentation for zombie tasks https://airflow.apache.org/docs/apache-airflow/stable/core-concepts/tasks.html#zombie-undead-tasks is a bit abstract at the moment. There is a scope for enhancing the document by explaining how Airflow detects tasks as zombies

### Solving the problem

We can enhance the documentation by translating this query https://github.com/astronomer/airflow/blob/main/airflow/jobs/scheduler_job_runner.py#L1721 to a layman readable text in our documentation.

### Anything else

It might also help to add developer contribution steps to reproduce zombies locally.

### Are you willing to submit PR?

- [ ] Yes I am willing to submit a PR!

### Code of Conduct

- [X] I agree to follow this project's [Code of Conduct](https://github.com/apache/airflow/blob/main/CODE_OF_CONDUCT.md)

"""Mark any "deferred" task as failed if the trigger or execution timeout has passed."""
        num_timed_out_tasks = session.execute(
            update(TI)
            .where(
                TI.state == TaskInstanceState.DEFERRED,
                TI.trigger_timeout < timezone.utcnow(),
            )
            .values(
                state=TaskInstanceState.SCHEDULED,
                next_method="__fail__",
                next_kwargs={"error": "Trigger/execution timeout"},
                trigger_id=None,
            )
        ).rowcount
        if num_timed_out_tasks:
            self.log.info("Timed out %i deferred tasks without fired triggers", num_timed_out_tasks)
    def _find_zombies(self) -> None: