mPDF error: IMAGE Error (https://maps.googleapis.com/maps/api/staticmap?zoom=13&size=640x400&markers=50.7138566,7.0420353&key=AIzaSyC5Qo-olxhcIPO50b7-b84SKdbo6b7u938): Error parsing image file - image type not recognised, and not supported by GD imagecreate