public GroupTopicPartitionData<PartitionIdLeaderEpochData> groupTopicPartitionData() {
        return groupTopicPartitionData;
    }
This class contains the parameters for {@link Persister#readSummary(ReadShareGroupStateSummaryParameters)}.
server-common/src/main/java/org/apache/kafka/server/group/share/ReadShareGroupStateSummaryParameters.java