Backport: Fix retries if the failure is due to missed heartbeats. tony-framework#451

PR: tony-framework#451

Author: zuston

tony-core/src/main/java/com/linkedin/tony/ApplicationMaster.java

@@ -692,6 +692,7 @@ private void reset() {
 
     // Reset the flag to track untracked processes.
     untrackedTaskFailed = false;
+    taskHasMissesHB = false;
 
     // Reset session
     session = sessionBuilder.build();