prevent container name reuse error for timeout flakes

tools/run_tests/jobset.py

@@ -272,6 +272,8 @@ class Job(object):
         message('TIMEOUT_FLAKE', self._spec.shortname, stdout, do_newline=True)
         self._timeout_retries += 1
         self.result.retries = self._timeout_retries + self._retries
+        if self._spec.kill_handler:
+          self._spec.kill_handler(self)
         self._process.terminate()
         self.start()
       else:

tools/run_tests/run_interop_tests.py

@@ -344,6 +344,11 @@ def add_auth_options(language, test_case, cmdline, env):
 def _job_kill_handler(job):
   if job._spec.container_name:
     dockerjob.docker_kill(job._spec.container_name)
+    # When the job times out and we decide to kill it,
+    # we need to wait a before restarting the job
+    # to prevent "container name already in use" error.
+    # TODO(jtattermusch): figure out a cleaner way to to this.
+    time.sleep(2)
 
 
 def cloud_to_prod_jobspec(language, test_case, docker_image=None, auth=False):