Fix incorrect formatting for code block

Author: samcole8

doc/topics/netapi/netapi-enable-clients.rst

@@ -81,6 +81,8 @@ in use, those should be listed in the Salt master config, under the
 
 Example configuration to enable only the local client interfaces:
 
+.. code-block:: yaml
+
     netapi_enable_clients:
       - local
       - local_async
@@ -90,6 +92,8 @@ Example configuration to enable only the local client interfaces:
 
 Example configuration to enable local client functionality and runners:
 
+.. code-block:: yaml
+
     netapi_enable_clients:
       - local
       - local_async