Add support to Chrome Driver in the official docker image

[wundo]

Currently, wraith already supports Chrome Driver (see #521 and PR #541) but the Docker image doesn't.

It would be great if we could use chrome with docker and don't have to worry about all the details of setting up headless chrome locally.

[freelock]

Trying to switch our testing containers over to use headless chrome with Wraith, and I'm hitting an issue trying to get chromedriver working correctly... I think it stems from our container running as root. It looks like the main thing needed is to pass --no-sandbox to Chrome so that it will start up -- is there any way to pass arguments like these into Wraith at this point?