---
upgrade:
  - |
    Format of APT keys has changed from simple list into dictionary. For
    ``base_apt_keys`` we now use name and key ids and for ``remote_apt_keys``
    names and URLs.

    This allows to instruct APT to use those keys only for their repositories
    instead of trusting them for all possible packages.

    If you override ``base_apt_keys`` or ``remote_apt_keys`` then please adapt
    to the new format.