public static void updateTopicConfig(String topic, Config newConfig) {
        ConcurrentHashMap<String, String> topicConfigs = FakeLocalMetadataStore.ALL_TOPICS.getOrDefault(topic, new ConcurrentHashMap<>());
        newConfig.entries().stream().forEach(configEntry -> {
            if (configEntry.name() != null) {
                if (configEntry.value() != null) {
                    log.debug("Topic '{}' update config '{}' to '{}'", topic, configEntry.name(), configEntry.value());
                    topicConfigs.compute(configEntry.name(), (key, value) -> configEntry.value());
                } else {
                    log.warn("Topic '{}' has config '{}' set to null", topic, configEntry.name());
                }
            }
        });
        FakeLocalMetadataStore.ALL_TOPICS.putIfAbsent(topic, topicConfigs);
    }
update topic configuration.
@param topic topic name
@param newConfig topic config
connect/mirror/src/test/java/org/apache/kafka/connect/mirror/clients/admin/FakeLocalMetadataStore.java