Broken if use remote chrome instance

[shinneider]

The error:

in user_agent_override.py has this code

if '--headless' in page.browser.process.args:
        override['acceptLanguage'] = locale or 'en-US,en'

but remote instances no has process...

Step to reproduce:

1. set up a chrome drive or docker (ex: https://hub.docker.com/r/browserless/chrome)

2. Use this snipet

browser = await connect(browserWSEndpoint='ws://127.0.0.1:3000')

page = await browser.newPage()
await stealth(page)

[shinneider]

In the master code, this bug is already fixed in this commit but no has release on pypi