Use tempfile instead of ad hoc temp dir creation.
Use tempfile instead of ad hoc temp dir creation.

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