The current LatestOnlyOperator will skip all downstream tasks blindly.
The doc shows a wrong behavior. It also shows an incorrect example about
the interaction between skipped tasks and trigger rules. I replace it with
another example using BranchingOperator in schedule level.
This fix can resolve this ticket:
https://issues.apache.org/jira/browse/AIRFLOW-3977
Also,
https://issues.apache.org/jira/browse/AIRFLOW-1784
Chen Tong