refactor: `storage` is not a sub-package of `persistence` - Aligned code

[demos/kafka/chat] / src / main / java / de / juplo / kafka / chat / backend / storage / mongodb / ChatRoomRepository.java

package de.juplo.kafka.chat.backend.storage.mongodb;

import org.springframework.data.mongodb.repository.MongoRepository;


public interface ChatRoomRepository extends MongoRepository<ChatRoomTo, String>
{
}