@Bean
    public LocaleResolver localeResolver() {
        AcceptHeaderLocaleResolver localeResolver = new AcceptHeaderLocaleResolver();
        localeResolver.setDefaultLocale(Locale.US);
        return localeResolver;
    }
@Test
    void resolveLocale_NoLocaleHeader() {
        LocaleConfig localeConfig = context.getBean(LocaleConfig.class);
        AcceptHeaderLocaleResolver localeResolver = (AcceptHeaderLocaleResolver) localeConfig.localeResolver();

        HttpServletRequest request = mock(HttpServletRequest.class);
        when(request.getHeader("Accept-Language")).thenReturn(null);

        Locale resolvedLocale = localeResolver.resolveLocale(request);
        assertEquals(Locale.US, resolvedLocale); // Assuming default is US
    }