static MultipartFile of(String name, String filename, Path path) {
        return of(name, filename, path, HttpHeaders.of());
    }
Creates a new {@link MultipartFile}.
@param name the name parameter of the {@code "content-disposition"}
@param filename the filename parameter of the {@code "content-disposition"}
                header.
@param path the path that stores the {@link BodyPart#content()}.
core/src/main/java/com/linecorp/armeria/common/multipart/MultipartFile.java