Confine Thunderbird with AppArmor

IMO, when we install Icedove from Debian, the AppArmor profile from the package should be installed and enforced by default. I can’t see the file in /etc/apparmor.d nor when running sudo aa-status. Tested in 2.7 and 3.0 (feature/stretch).

Feature Branch: tails:feature/11973-enable-thunderbird-apparmor-profile icedove:tails/stretch

Related issues

Related to #15395 (closed)
Related to #11964 (closed)
Blocked by #11712 (closed)
Blocks #13245 (closed)

Original created by @u on 11973 (Redmine)

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