Fixing HttpClient warning “Invalid expires attribute” using fluent API

The default HttpClient has difficulty understanding the latest RFC-compliant headers.

Instead of hiding the warning, just switch to a standard cookie spec like this (HttpClient 4.4+):

HttpClient httpClient = HttpClients.custom()
        .setDefaultRequestConfig(RequestConfig.custom()
                .setCookieSpec(CookieSpecs.STANDARD).build())
        .build();