ACK/APPLIED/cmnt: [PATCH][autotest-client-tests] UBUNTU: SAUCE: ubuntu_qrt_apparmor: on Groovy+, invoke the test using python3

[Po-Hsu Lin]

One small note, platform.dist() has been deprecated since python 3.5
Since we might need to migrate from python2 to python3 for our testing
infrastructure one day in the future, for the long term perspective
it's safter to use the following:

   try:
       series = platform.dist()[2]
   except AttributeError:
       import distro
       series = distro.codename()

Thanks for the fix, ACK'd, applied and pushed.
Sam