The runtime image was using a very old Alpine version.
This caused issues with the catatonit install
Now using the Balena armv7hf Alpine image for this.
With some apt/dpkg magic building multidb containers for arm versions
now also works. As long as the build stage and docker-image stage use
the same base (debian buster now) it should all work.
Resolves #530, resolves #1066
