public static Optional<String> extract(final HttpServletRequest request) {
        String header = request.getHeader(AUTHORIZATION_HEADER);

        if (!StringUtils.hasText(header)) {
            return Optional.empty();
        }

        return extractFromHeader(header.split(HEADER_SPLIT_DELIMITER));
    }
@Test
    void 토큰_헤더가_없다면_빈_값이_반환된다() {
        // given
        when(request.getHeader(AUTHORIZATION_HEADER)).thenReturn("InvalidType token");

        // when
        Optional<String> result = AuthenticationExtractor.extract(request);

        // then
        assertThat(result).isEmpty();
    }