DOCS-14765 Add Extra code examples for rs.reconfig()

Author: ianf-mongodb

source/reference/method/rs.reconfig.txt

@@ -180,6 +180,9 @@ A replica set named ``rs0`` has the following configuration:
       }
    }
 
+Change Replica Set Member Priority
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
 The following sequence of operations updates the
 :rsconf:`members[n].priority` of the second member.
 The operations are issued through a :binary:`~bin.mongo` shell connected to
@@ -275,7 +278,25 @@ the primary.
       }
    }
 
-.. seealso:: 
+Change Replica Set Settings
+~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+You can also modify the cluster replica set :rsconf:`settings` document.
+The :rsconf:`settings` document contains configuration options that 
+apply to the whole replica set.
+
+The following sequence of operations updates the 
+:rsconf:`settings.heartbeatTimeoutSecs` of the cluster to ``15``.
+The operations are issued through a :binary:`~bin.mongosh` session 
+that is connected to the primary.
+
+.. code-block:: javascript
+
+   cfg = rs.conf();
+   cfg.settings.heartbeatTimeoutSecs = 15;
+   rs.reconfig(cfg);
+
+.. seealso::
 
    - :method:`rs.conf()`