open fun rxOffsetsForTimes(topicPartition: TopicPartition, timestamp: Long): Single<OffsetAndTimestamp>
Look up the offset for the given partition by timestamp. Note: the result might be null in case for the given timestamp no offset can be found -- e.g., when the timestamp refers to the future
topicPartition - TopicPartition to query.
timestamp - Timestamp to be used in the query.
Return