Enable private repositories

[alexandervalencia]

Currently it's not possible to render private repositories because phantom needs to input credentials. This is a request to add the ability to render private repositories the user has access to. They would input their credentials at the initial prompt (which would replace the need to get an access token.) and they would be used to login the phantom instance.

[gcamp]

Very quick fix for those who want to make it work quickly just add the cookie lines here

const page = await browser.newPage();

/// add those 2 lines below
var cookie = [...]
await page.setCookie(...cookie)

Create cookies from your GitHub login as described here