HIVE-8794: Hive on Tez leaks AMs when killed before first dag is run (Gunther Hagleitner, reviewed by Gopal V)

git-svn-id: https://svn.apache.org/repos/asf/hive/branches/branch-0.14@1637601 13f79535-47bb-0310-9956-ffa450edef68