chore(examples): update search example (#1181)

The search bar was not fully loaded and therefore "puppeteer" could not be entered into the submit field.

This patch starts waiting for the input element to be rendered to ensure this
element is loaded before attempting to populate it.

examples/search.js

@@ -23,6 +23,8 @@ const puppeteer = require('puppeteer');
 const browser = await puppeteer.launch();
 const page = await browser.newPage();
 await page.goto('https://google.com', {waitUntil: 'networkidle2'});
+
+await page.waitFor('input[name=q]');
 // Type our query into the search bar
 await page.type('input[name=q]', 'puppeteer');