fix typo in tutorial/managed-chained-replication.txt

Author: jrassi

source/tutorial/manage-chained-replication.txt

@@ -15,7 +15,7 @@ Chained replication can reduce load on the primary. But chained
 replication can also result in increased replication lag, depending on
 the topology of the network.
 
-.. versionadded:: 2.
+.. versionadded:: 2.2.2
 
 You can use the :data:`~local.system.replset.settings.chainingAllowed`
 setting in :doc:`/reference/replica-configuration` to disable chained