Adds missing keys specific to the nodejs implementation (#49703)
Adds missing keys specific to the nodejs implementation (#49703)

See https://github.com/devongovett/node-wkhtmltopdf/blob/master/index.js#L28

Co-authored-by: Jasper Jansen <af3a4f12ca527d012127cd060074a4c3348cdbc2@voltolabs.com>
georgemarshall/DefinitelyTyped,markogresak/DefinitelyTyped,georgemarshall/DefinitelyTyped,georgemarshall/DefinitelyTyped,georgemarshall/DefinitelyTyped