Fix unit tests under Jenkins
Fix unit tests under Jenkins

os.getlogin() was throwing:
  OSError: [Errno 25] Inappropriate ioctl for device

Signed-off-by: Zack Cerza <f801c831581d4150a2793939287636221d62131e@inktank.com>

michaelsevilla/teuthology,dmick/teuthology,michaelsevilla/teuthology,SUSE/teuthology,SUSE/teuthology,dmick/teuthology,ktdreyer/teuthology,t-miyamae/teuthology,caibo2014/teuthology,SUSE/teuthology,ktdreyer/teuthology,yghannam/teuthology,yghannam/teuthology,dreamhost/teuthology,ceph/teuthology,zhouyuan/teuthology,robbat2/teuthology,tchaikov/teuthology,tchaikov/teuthology,dmick/teuthology,caibo2014/teuthology,ceph/teuthology,dreamhost/teuthology,t-miyamae/teuthology,ivotron/teuthology,robbat2/teuthology,zhouyuan/teuthology,ivotron/teuthology