mPDF error: IMAGE Error (https://chart.googleapis.com/chart?chs=300x300&cht=qr&chl=https://newenglandautomall.com/cars-for-sale/2017-audi-q7-3-0t-quattro-premium-plus-awd-4dr-suv-pawtucket-ri-1869120/&choe=UTF-8): Error parsing image file - image type not recognised, and not supported by GD imagecreate