DOCS-11409: clone command missing in example

Author: kay-kim

source/reference/command/clone.txt

@@ -69,4 +69,4 @@ issue the :method:`db.runCommand()`.
 .. code-block:: javascript
 
    use marketing
-   db.runCommand( "db1.example.net:27017")
+   db.runCommand( { clone: "db1.example.net:27017" })