public HttpClientBuilder apacheBuilder() {
        HttpClientBuilder builder = HttpClientBuilder.create();
        addSslSocketFactory(builder, new HttpClientConnectionManagerFactoryProxy(), hostnameVerifier);
        if (rewriteHttpToHttps)
            addHttpsRewritingRoutePlanner(builder);

        builder.disableConnectionState(); // Share connections between subsequent requests.
        builder.disableCookieManagement();
        builder.disableAuthCaching();
        builder.disableRedirectHandling();

        return builder;
    }
Sync HTTP client builder <em>for internal Vespa communications over http/https.</em>
Configures Vespa mTLS and handles TLS mixed mode automatically.
Custom connection managers must be configured through {@link #connectionManagerFactory(HttpClientConnectionManagerFactory)}.

@author jonmv
http-utils/src/main/java/ai/vespa/util/http/hc5/VespaHttpClientBuilder.java