changed thread pool code again

backend/tools/simple_state_checker.py

@@ -144,10 +144,8 @@ with ThreadPool(NUM_THREADS) as pool:
     except TimeoutError as e:
         logger.error("Timeout while getting capture agent state! {}".format(e))
 
-pool.close()
-pool.join()
+logger.info("DONE checking capture agents / recorders!")
+
 logged_events = rec_err_state_log_stream.getvalue()
 if len(logged_events) > 0:
     send_error_mail(logged_events, "Errors have been detected while checking recorder states!")
-
-logger.info("DONE checking capture agents / recorders!")