typo on rs.add example

Author: kay-kim

source/reference/method/rs.add.txt

@@ -165,7 +165,7 @@ the host ``mongodb3.example.net`` and accessible on the default port
 
   .. code-block:: javascript
 
-     rs.add("mongodb3.example.net:27017"'", true)
+     rs.add("mongodb3.example.net:27017", true)
 
 .. include:: /includes/extracts/arbiters-and-pvs-with-reference.rst