Updating tests to use the new responseBody signature

lib/util.js

@@ -405,6 +405,10 @@ module.exports = {
    * @returns {string} string
    */
   insertSpacesInName: function (string) {
+    if (!string) {
+      return null;
+    }
+
     // convert createUser to create User
     string = string.replace(/([a-z])([A-Z])/g, '$1 $2');