public static Config getConfig(
            Configuration configuration, @Nullable HostAndPort externalAddress) {
        return getConfig(
                configuration,
                externalAddress,
                null,
                PekkoUtils.getForkJoinExecutorConfig(
                        ActorSystemBootstrapTools.getForkJoinExecutorConfiguration(configuration)));
    }
@Test
    void getConfigSslEngineProviderWithCertFingerprint() {
        final Configuration configuration = new Configuration();
        configuration.set(SecurityOptions.SSL_INTERNAL_ENABLED, true);

        final String fingerprint = "A8:98:5D:3A:65:E5:E5:C4:B2:D7:D6:6D:40:C6:DD:2F:B1:9C:54:36";
        configuration.set(SecurityOptions.SSL_INTERNAL_CERT_FINGERPRINT, fingerprint);

        final Config config =
                PekkoUtils.getConfig(configuration, new HostAndPort("localhost", 31337));
        final Config sslConfig = config.getConfig("pekko.remote.classic.netty.ssl");

        assertThat(sslConfig.getString("ssl-engine-provider"))
                .isEqualTo("org.apache.flink.runtime.rpc.pekko.CustomSSLEngineProvider");
        assertThat(sslConfig.getStringList("security.cert-fingerprints")).contains(fingerprint);
    }