What's Changed
* Add tests, fixes 22 by timkpaine in https://github.com/airflow-laminar/airflow-ha/pull/38
* Switch terminology to reference date, default to data_interval_end by timkpaine in https://github.com/airflow-laminar/airflow-ha/pull/39
**Full Changelog**: https://github.com/airflow-laminar/airflow-ha/compare/v1.2.2...v1.3.0