private static String getCertificate(ConnectorConfig.Ssl config) {
        if(!config.certificate().isBlank()) return config.certificate();
        return readToString(config.certificateFile());
    }
An implementation of {@link SslProvider} that uses the {@link ConnectorConfig} to configure SSL.

@author bjorncs
container-core/src/main/java/com/yahoo/jdisc/http/ssl/impl/ConfiguredSslContextFactoryProvider.java