async_cluster: add pipeline support (redis#2199)

Co-authored-by: dvora-h <67596500+dvora-h@users.noreply.github.com>

Author: utkarshgupta137

docs/connections.rst

@@ -76,6 +76,11 @@ ClusterNode (Async)
 .. autoclass:: redis.asyncio.cluster.ClusterNode
  :members:
 
+ClusterPipeline (Async)
+===================
+.. autoclass:: redis.asyncio.cluster.ClusterPipeline
+ :members:
+
 
 Connection
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