fix: typo in Johnzon name

Signed-off-by: Jean-Louis Monteiro <jlmonteiro@tomitribe.com>
diff --git a/src/site/markdown/index.md b/src/site/markdown/index.md
index 324684d..0cc87b8 100644
--- a/src/site/markdown/index.md
+++ b/src/site/markdown/index.md
@@ -369,13 +369,13 @@
 
 <pre class="prettyprint linenums"><![CDATA[
 final JsonValueReader<Simple> reader = new JsonValueReader<>(Json.createObjectBuilder().add("value", "simple").build());
-final Jsonb jsonb = getJohnsonJsonb();
+final Jsonb jsonb = getJohnzonJsonb();
 final Simple simple = jsonb.fromJson(reader, SomeModel.class);
 ]]></pre>
 
 <pre class="prettyprint linenums"><![CDATA[
 final JsonValueWriter writer = new JsonValueWriter();
-final Jsonb jsonb = getJohnsonJsonb();
+final Jsonb jsonb = getJohnzonJsonb();
 jsonb.toJson(object, writer);
 final JsonObject jsonObject = writer.getObject();
 ]]></pre>