Add Deseret Digital Media to list of "who uses Airflow"

[formigone]

Add Deseret Digital Media to list of "Who uses Apache Airflow." Short and sweet. DDM is the company that owns and operates the websites www.ksl.com, www.utah.com, and www.thememories.com. These are major properties in Utah, where the classifieds product of ksl.com is far more popular to that market than any other competitor, including Facebook and Craigslist.

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[boring-cyborg]

Congratulations on your first Pull Request and welcome to the Apache Airflow community! If you have any issues or are unsure about any anything please check our Contribution Guide (https://github.com/apache/airflow/blob/master/CONTRIBUTING.rst)
Here are some useful points:

• Pay attention to the quality of your code (flake8, pylint and type annotations). Our pre-commits will help you with that.
• In case of a new feature add useful documentation (in docstrings or in docs/ directory). Adding a new operator? Check this short guide Consider adding an example DAG that shows how users should use it.
• Consider using Breeze environment for testing locally, it’s a heavy docker but it ships with a working Airflow and a lot of integrations.
• Be patient and persistent. It might take some time to get a review or get the final approval from Committers.
• Be sure to read the Airflow Coding style.
  Apache Airflow is a community-driven project and together we are making it better 🚀.
  In case of doubts contact the developers at:
  Mailing List: dev@airflow.apache.org
  Slack: https://apache-airflow-slack.herokuapp.com/

[boring-cyborg]

Awesome work, congrats on your first merged pull request!

[mik-laj]

@formigone Thanks for the contribution. What is your next step? What would you like to improve in Airflow?