Data-driven test case that renders the HTML files into an 800x600 image for baseline comparison. Task-number: QTBUG-99148 Pick-to: 6.3 Change-Id: I9ccc0cd21a1e94ff68d23bb82b84e1da46d6335a Reviewed-by: Eirik Aavitsland <eirik.aavitsland@qt.io>