why image file extention removed?

why image file extension removed when I use cloudinary react?
but nodejs api contains file extension, for example ".jpg"

`export default function AvatarImage({ photo, width, height }) {

const { public_id: publicId, version } = photo;
const cloudinaryImage = cld.image(publicId);

cloudinaryImage
.resize(scale().width(width).height(height));

return (

);
}`