Apache Airflow 2.2.0beta2 available for testing

[Jed Cunningham <je...@astronomer.io.INVALID>]

Hey fellow Airflowers,

We have cut Airflow 2.2.0beta2 with more new features and bug fixes.

This "snapshot" is intended for members of the Airflow developer community
to test the build and allow early testing of 2.2.0. Please test this beta
and create GitHub issues wherever possible if you encounter bugs
(use 2.2.0b2 in the version dropdown when creating the issue).

For clarity, this is not an official release of Apache Airflow - that
doesn't happen until we make a release candidate and then vote on that.

As I’m not a member of the PMC, Kaxil signed the distribution.

The beta snapshot is available at:
https://dist.apache.org/repos/dist/dev/airflow/2.2.0b2/

*apache-airflow-2.2.0b2-source.tar.gz* is a source release that comes with
INSTALL instructions.
*apache-airflow-2.2.0b2.tar.gz* is the binary Python "sdist" snapshot.
*apache_airflow-2.2.0b2-py3-none-any.whl* is the binary Python wheel
snapshot.

This snapshot has been pushed to PyPI too at
https://pypi.org/project/apache-airflow/2.2.0b2/ and can be installed by
running the following command:

pip install 'apache-airflow==2.2.0b2'

*Constraints files* are available at
https://github.com/apache/airflow/tree/constraints-2.2.0b2

*Full Changelog*:
https://github.com/apache/airflow/blob/2.2.0b2/CHANGELOG.txt

*New features since 2.2.0b1:*

   - Add a Docker Taskflow decorator (#15330)
   - Add docs for AIP 39: Timetables (#17552)
   - Display alert messages on dashboard from local settings (#18284)
   - Show Triggers table in Webserver (#17876)
   - Advanced Params using json-schema (#17100)
   - Add some basic metrics to the Triggerer (#18214)

Thanks,
Jed