docs: added comments to the readme (#10552)

Co-authored-by: Alex Rudenko <OrKoN@users.noreply.github.com>

README.md

@@ -143,9 +143,11 @@ The following example searches [developer.chrome.com](https://developer.chrome.c
 import puppeteer from 'puppeteer';
 
 (async () => {
+  // Launch the browser and open a new blank page
   const browser = await puppeteer.launch();
   const page = await browser.newPage();
 
+  // Navigate the page to a URL
   await page.goto('https://developer.chrome.com/');
 
   // Set screen size