Update puppeteerArgs type in README.md

[Steve0929]

Fixed puppeteerArgs type, it should be an array of strings as per puppeteer also added usage example.

[frinyvonnick]

Hi @Steve0929 👋

puppeteerArgs is the whole object passed to the launch function and not only the args passed to Chromium. So it is object but maybe the description of the property is misguiding 🤔 How could we improve it?

[Steve0929]

Ohh you are right, I think my confussion came from the naming, maybe using the same name: puppeteerOptions that is passed to Cluster.launch instead of puppeteerArgs could be clearer 🤔. I think we can close this for now, thanks!