This is a feature release.
Features
--------
* Use ``flatpaks/`` namespace for Flatpaks, and make it configurable.
(2924, 3052).
* Add json response handler for server internal errors (3035).
Bug fixes
---------
* Fix HTTP 500 errors when viewing composes (2826).
* Set log level to ERROR in bodhi-approve-testing (3021).
Development improvements
------------------------
* Log why buildroot overrides are expired (3060).