v2021 ← v2022dev2: Drop the dependency on the LGPL-3 libtdb
requested to merge wip/em/v2021-licensing-drop-dependency-on-lgpl3-libtdb into apertis/v2021-updates
Use the simple backend as gdbm is LGPL-3 as well, which is unfit for
packages in the target component.
Backport of !16 (merged)
Task: T7887