Debian 11 "bullseye" released - use of "stable" in release name for /etc/apt/sources.list

This is not recommended now: it does cause a massive flag day when releases change. If you hard code the release code name, it will follow all through from unstable -> testing -> stable -> oldstable -> oldoldstable for 5+ years support. It also does mitigate against
links not catching up, too.