Block / Frobid a package installation on Debian

Try to block apparmor automatic install everything doing apt dist-upgrade.

Create a file: /etc/apt/preferences.d/99-apparmor

Package: apparmor
Pin: release *
Pin-Priority: -1

Reference: https://wiki.debian.org/AptConfiguration#Prevent.2Fselective_installation_from_third-party_a_repository