fix(@schematics/angular): use baseUrl for default e2e test

replace usage of `'/'` for default end-to-end test by `browser.baseUrl`
to take into account any accesspath and rely on provided setting.

Author: loganmzz

packages/schematics/angular/e2e/files/src/app.po.ts.template

@@ -2,7 +2,7 @@ import { browser, by, element } from 'protractor';
 
 export class AppPage {
   navigateTo() {
-    return browser.get('/') as Promise<any>;
+    return browser.get(browser.baseUrl) as Promise<any>;
   }
 
   getTitleText() {

tests/angular_devkit/build_angular/hello-world-app/e2e/app.po.ts

@@ -9,7 +9,7 @@ import { browser, by, element } from 'protractor';
 
 export class AppPage {
   navigateTo() {
-    return browser.get('/');
+    return browser.get(browser.baseUrl);
   }
 
   getTitleText() {