docs(aio): Upgrade examples to Angular 6 (#23234)

PR Close #23234

aio/tools/examples/shared/boilerplate/cli/e2e/src/app.po.ts

@@ -0,0 +1,11 @@
+import { browser, by, element } from 'protractor';
+
+export class AppPage {
+  navigateTo() {
+    return browser.get('/');
+  }
+
+  getParagraphText() {
+    return element(by.css('app-root h1')).getText();
+  }
+}