`meltano elt` should not run again when previous run lasts longer than the interval and hasn't completed yet

As brought up by Niall Woodward on Slack:

How does Meltano behave when a run is started before the previous has completed? I can't find that in the docs. Example where this could happen is with a scheduler running hourly and a run that takes over an hour

Tom Ellif suggested:

this would just be an airflow thing right? If so does https://stackoverflow.com/a/57229106/2291321 answer that for you?

That post suggests that we should set either depends_on_past=True or max_active_runs=1.