Add try_mark_run_dead()
Add try_mark_run_dead()

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

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