[apparmor] KUnit and experimental e2e tests

[Eric Chiang]

Hey everyone,

Mike Salvatore's been working on a KUnit[1] patch set for the AppArmor
subsystem. I'd like to setup some public CI so we can actively running
these and potentially test other proposed patches.

Would anyone be opposed to setting up a gitlab.com/apparmor/linux
mirror, creating a kunit branch and configuring GitLab CI? Short term,
we could start throwing patches at the branch for testing, and log
term as KUnit is upstreamed[2] we'd look to formalize unit test
requirements for AppArmor code changes.

Separately, I've been working on an experimental tool for writing e2e
tests for arbitrary apparmor_parser / kernel combinations leveraging
QEMU. I'd like to start some discussion if it'd be a good addition to
the existing tests/regression/apparmor suite. Would it be okay to open
source that under gitlab.com/apparmor/apparmor_e2e?

[1] https://google.github.io/kunit-docs/third_party/kernel/docs/
[2] https://lkml.org/lkml/2019/3/4/1019

Eric