Fix codec code bug (#605)

Author: jordan-smith721

source/fundamentals/data-formats/codecs.txt

@@ -176,7 +176,7 @@ from the prior example using the following code:
 .. code-block:: java
    :copyable: true
 
-   Codec<String> powerStatusCodec = codecRegistry.get(String.class);
+   Codec<PowerStatus> powerStatusCodec = codecRegistry.get(PowerStatus.class);
    Codec<Integer> integerCodec = codecRegistry.get(Integer.class);
 
 If you attempt to retrieve a ``Codec`` instance for a class that is not