test: asserts feature snippet and parsed data in "data_model" tests

test/cucumber/step_definitions/model_steps.js

@@ -24,26 +24,20 @@ module.exports = function() {
   return this.Then(
     /^"([^"]*)" JSON representation will look like this:$/,
     function(objectTypeString, string, callback) {
-      let data, klass;
+      let data;
       const expectedObject = JSON.parse(string);
 
       if (objectTypeString === 'HTTP Request') {
-        klass = 'HttpRequest';
         data = this.model.request;
       } else if (objectTypeString === 'HTTP Response') {
-        klass = 'HttpResponse';
         data = this.model.response;
       } else if (objectTypeString === 'Expected HTTP Request') {
-        klass = 'ExpectedHttpRequest';
         data = this.expected;
       } else if (objectTypeString === 'Expected HTTP Response') {
-        klass = 'ExpectedHttpResponse';
         data = this.expected;
       }
 
-      const instance = new gavel[klass](data);
-
-      const jsonizedInstance = JSON.parse(JSON.stringify(instance));
+      const jsonizedInstance = JSON.parse(JSON.stringify(data));
 
       if (!deepEqual(expectedObject, jsonizedInstance, { strict: true })) {
         callback(