In a classic system, when running a confinement:strict snap, most of your /etc/ inside the snap is the /etc from the classic system. This includes both /etc/lsb-release and /etc/os-release.
However, /etc/os-release is a symlink to ../usr/lib/os-release, which when inside the snap is the core snap's. We'll be explicitly mounting the "outside" os-release over that symlink to make this kind of thing work.
In a classic system, when running a confinement:strict snap, most of your /etc/ inside the snap is the /etc from the classic system. This includes both /etc/lsb-release and /etc/os-release.
However, /etc/os-release is a symlink to ../usr/ lib/os- release, which when inside the snap is the core snap's. We'll be explicitly mounting the "outside" os-release over that symlink to make this kind of thing work.