Implement generic database connection

[sbernauer]

Same as stackabletech/airflow-operator#64 but for hive-operator

[lfrancke]

There are so many issues and PRs... I can't find the release notes. I see the PR has the label but I can't find the actual release notes.

[sbernauer]

It's now here: #674 (comment)

[sbernauer]

I added release notes for all affected products: Airflow, Superset, Hive, (Trino and Druid already were)