@Override
    public ArmeriaResteasyClientBuilder keyStore(KeyStore keyStore, char[] password) {
        delegate.keyStore(keyStore, password);
        return this;
    }
Armeria does not allow to access the ssl-context from WebClient API.
This functionality must be achieved by configuring {@link com.linecorp.armeria.client.WebClientBuilder}.
@throws UnsupportedOperationException always
resteasy/src/main/java/com/linecorp/armeria/client/resteasy/ArmeriaResteasyClientBuilder.java