public PulsarSourceBuilder<OUT> setTopics(List<String> topics) {
        ensureSubscriberIsNull("topics");
        List<String> distinctTopics = TopicNameUtils.distinctTopics(topics);
        this.subscriber = PulsarSubscriber.getTopicListSubscriber(distinctTopics);
        return this;
    }
Set a pulsar topic list for the flink source. Some topics may not exist currently, consuming
this non-existed topic wouldn't throw any exception. But the best solution is just consuming
by using a topic regex. You can set topics once either with {@link #setTopics} or {@link
#setTopicPattern} in this builder.

@param topics The topic list you would like to consume messages.
@return this PulsarSourceBuilder.
inlong-sort/sort-flink/sort-flink-v1.18/sort-connectors/pulsar/src/main/java/org/apache/inlong/sort/pulsar/source/PulsarSourceBuilder.java