ci: Exclude broken Stem tests

[tor.git] / changes / ticket40799

  o Minor bugfixes (sandbox):
    - Allow membarrier for the sandbox. And allow rt_sigprocmask when compiled
      with LTTng. Fixes bug 40799; bugfix on 0.3.5.1-alpha.

  o Minor feature (CI):
    - Update CI to use Debian Bullseye for runners.