build(deps-dev): bump apache-airflow from 2.8.3 to 2.8.4

Bumps [apache-airflow](https://github.com/apache/airflow) from 2.8.3 to 2.8.4.
- [Release notes](https://github.com/apache/airflow/releases)
- [Changelog](https://github.com/apache/airflow/blob/main/RELEASE_NOTES.rst)
- [Commits](apache/airflow@2.8.3...2.8.4)

---
updated-dependencies:
- dependency-name: apache-airflow
  dependency-type: direct:development
...

Signed-off-by: dependabot[bot] <[email protected]>