(cherry picked from commit a54a784168c023d1f95c2c1ba0cd97659ffbd08c)

# Conflicts:
#	core/admin/Dockerfile
#	core/dovecot/Dockerfile
#	core/nginx/Dockerfile
#	core/none/Dockerfile
#	core/postfix/Dockerfile
#	optional/clamav/Dockerfile
#	optional/fetchmail/Dockerfile
#	optional/radicale/Dockerfile
#	optional/unbound/Dockerfile
#	setup/Dockerfile

- Moved run to bottom of Dockerfile to allow using unmodified / cached states.
- Simplified bash code in deploy.sh.
- Improved the large bash one-liner in CI.yml. It could not handle >9 for 1.x.

Co-authored-by: Dario Ernst <github@kanojo.de>

- remove ==2.1.12 in Dockerfile pip3 install radicale
- remove -f flag in Dockerfile CMD
- remove deprecated daemon and dns_lookup settings from radicale.conf
- move realm setting from [server] to [auth] in radicale.conf
- add newsfragment

As 3.0 is breaking compatibility with 2.1 branch

Required to fix failing builds caused by [alpine]upstream package rebuild against different python version

This reverts commit c787e4bd.

This fix https://github.com/Mailu/Mailu/issues/918

Bash shell is used by default in Kubernetes' dashboard console, which is very
useful for admins.

Radicale supports automatic versioning of calendar event changes if a git repository was initialized in the data directory. For this to work, Radicale needs dulwich as an interface to the git repository.

http://radicale.org/user_documentation/#idgit-support