docs(troubleshooting): recommend using args for heroku (#5197)

Co-Authored-By: Mathias Bynens <mathias@qiwi.be>

docs/troubleshooting.md

@@ -408,6 +408,8 @@ Running Puppeteer on Heroku requires some additional dependencies that aren't in
 
 The url for the buildpack is https://github.com/jontewks/puppeteer-heroku-buildpack
 
+Ensure that you're using `'--no-sandbox'` mode when launching Puppeteer. This can be done by passing it as an argument to your `.launch()` call: `puppeteer.launch({ args: ['--no-sandbox'] });`.
+
 When you click add buildpack, simply paste that url into the input, and click save. On the next deploy, your app will also install the dependencies that Puppeteer needs to run.
 
 If you need to render Chinese, Japanese, or Korean characters you may need to use a buildpack with additional font files like https://github.com/CoffeeAndCode/puppeteer-heroku-buildpack