qa/tasks: watchdog terminate thrasher

If a thrasher exception occurs, the do_dump_ops thread will continue
looping until the Teuthology timeout is reached.
The watchdog should terminate the thrasher to free up resources.

Fixes: https://tracker.ceph.com/issues/66698
Signed-off-by: Nitzan Mordechai <[email protected]>

Author: NitzanMordhai

qa/tasks/daemonwatchdog.py

@@ -117,6 +117,7 @@ def watch(self):
             for thrasher in self.thrashers:
                 if thrasher.exception is not None:
                     self.log("{name} failed".format(name=thrasher.name))
+                    thrasher.stop_and_join()
                     bark = True
 
             if bark: