BB: Pass generator instead of list comprehension to all()

This will allow a short-circuit.

envs/monkey_zoo/blackbox/island_client/monkey_island_client.py

@@ -172,4 +172,4 @@ def get_test_query_results(response):
 
     def is_all_monkeys_dead(self):
         agents = self.get_agents()
-        return all([a.stop_time is not None for a in agents])
+        return all((a.stop_time is not None for a in agents))