Fix getattr propagation to wrapped stream (#711)

Author: vgvoleg

ydb/aio/connection.py

@@ -127,6 +127,9 @@ async def __anext__(self):
                 await self.on_disconnected_callback()
             raise ydb_error
 
+    def __getattr__(self, item):
+        return getattr(self.resp, item)
+
 
 class Connection:
     __slots__ = (

ydb/connection.py

@@ -363,6 +363,9 @@ def __next__(self):
                 self.on_disconnected_callback()
             raise ydb_error
 
+    def __getattr__(self, item):
+        return getattr(self.resp, item)
+
 
 class Connection(object):
     __slots__ = (