feat: Add listener notification in API endpoint when skipped

[kacpermuda]

Given that new listener method on_task_instance_skipped was added in #59467, we should add listener invocation in task state api endpoint, similar to success and failure states added in #48941. Also updating listeners doc with this new method, since the implementing PR did not contain doc update.

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[pierrejeambrun]

LGTM

[kacpermuda]

Thanks, the remote logging test failure seems unrelated

[pierrejeambrun]

I just restarted the failed job. lets see if it's flaky

[kacpermuda]

Yup, passed now, thanks