Update checkbox_tree.md

Author: cskevint

checkbox_tree.md

@@ -89,11 +89,13 @@ __The purpose of this test is to determine your ability to create custom compone
 ### Data Load and Transformation
 
 1. Perform an ajax call like so:    
-<pre>$.ajax({
-    url: "https://rawgit.com/cskevint/interview/master/checkbox_tree.json"
-}).done(function (result) {
-    $(document.body).append(JSON.stringify(result));
-});</pre>
+
+    $.ajax({
+        url: "https://rawgit.com/cskevint/interview/master/checkbox_tree.json"
+    }).done(function (result) {
+        $(document.body).append(JSON.stringify(result));
+    });
+
 2. This will call a __window.data__ function with the resulting JSON string as the argument.
 3. You will need to parse it and transform it to look like the structure above as _input for the component_.