Keeps why a run failed: the action's error argument in words
(MishkaCmsMigration.Report.reason/1) as the run's reason. The error is what AshOban hands its
trigger's on_error action after the last attempt, or what Oban says of a job it discarded.
update :fail do
argument :error, :term, allow_nil?: false
change MishkaCmsMigration.Resources.Changes.Reason
end