fix: remove typescript references to d.ts files from benchpress and e2e tests

using "/// <reference" is incorrect because it makes our code non-portable. The correct solution is to provide
these typings as ambient typings as an additional entry point - which we already do.

Closes #8050

modules/benchpress/test/firefox_extension/conf.ts

@@ -1,4 +1,3 @@
-/// <reference path="../../../angular2/typings/node/node.d.ts" />
 require('es6-shim/es6-shim.js');
 require('reflect-metadata');
 var testHelper = require('../../src/firefox_extension/lib/test_helper.js');

modules/benchpress/test/firefox_extension/spec.ts

@@ -1,7 +1,3 @@
-/// <reference path="../../../angular2/typings/node/node.d.ts" />
-/// <reference path="../../../angular2/typings/angular-protractor/angular-protractor.d.ts" />
-/// <reference path="../../../angular2/typings/jasmine/jasmine.d.ts" />
-
 var assertEventsContainsName = function(events, eventName) {
   var found = false;
   for (var i = 0; i < events.length; ++i) {