set default response_callbacks to redis.asyncio.cluster.ClusterNode (#2201)

* set default response_callbacks to redis.asyncio.cluster.ClusterNode

* add test case for ClusterNode class

* fix lint error

* merge test case into `test_startup_nodes`

Author: rapidia

redis/asyncio/cluster.py

@@ -725,7 +725,7 @@ def __init__(
         server_type: Optional[str] = None,
         max_connections: int = 2 ** 31,
         connection_class: Type[Connection] = Connection,
-        response_callbacks: Dict = None,
+        response_callbacks: Dict = RedisCluster.RESPONSE_CALLBACKS,
         **connection_kwargs,
     ) -> None:
         if host == "localhost":

tests/test_asyncio/test_cluster.py

@@ -244,6 +244,11 @@ async def test_startup_nodes(self) -> None:
 
         await cluster.close()
 
+        startup_nodes = [ClusterNode("127.0.0.1", 16379)]
+        async with RedisCluster(startup_nodes=startup_nodes) as rc:
+            assert await rc.set("A", 1)
+            assert await rc.get("A") == b"1"
+
     async def test_empty_startup_nodes(self) -> None:
         """
         Test that exception is raised when empty providing empty startup_nodes