Java client: receive pubsub messages

[Yury-Fridlyand]

Based on #381

Configuration with callback:

    @Test
    @SneakyThrows
    public void basic_client() {
        BiConsumer<Message, Object> callback =
            (msg, context) -> System.out.printf("Received %s, context %s\n", msg, context);

        var regularClient =
                RedisClient.CreateClient(
                                RedisClientConfiguration.builder()
                                        .address(NodeAddress.builder().port(6379).build())
                                        .requestTimeout(3000)
                                        .subscriptionConfiguration(
                                                StandaloneSubscriptionConfiguration.builder()
                                                        .subscription(EXACT, "ch1")
                                                        .subscription(PATTERN, "chat*")
                                                        .callback(callback)
                                                        .build())
                                        .build())
                        .get();

        Thread.sleep(100500);
    }

To send messages use redis-cli: publish ch1 $message

Configuration without callback:

    @Test
    @SneakyThrows
    public void basic_client() {
        var regularClient =
                RedisClient.CreateClient(
                                RedisClientConfiguration.builder()
                                        .address(NodeAddress.builder().port(6379).build())
                                        .requestTimeout(3000)
                                        .subscriptionConfiguration(
                                                StandaloneSubscriptionConfiguration.builder()
                                                        .subscription(EXACT, "ch1")
                                                        .subscription(PATTERN, "chat*")
                                                        .build())
                                        .build())
                        .get();

        Thread.sleep(100500);

        Message msg = null;
        while ((msg = regularClient.tryGetPubSubMessage()) != null) {
            System.out.printf("Received from queue %s\n", msg);
        }
    }

[Yury-Fridlyand]

Moved from Value::Array handling from above

[acarbonetto]

why "try"? what is the purpose of this method vs getPubSubMessage?

[Yury-Fridlyand]

I followed python client namings: https://github.com/aws/glide-for-redis/pull/1616/files#diff-f0f69819afe466c0f3e8afd4ea2fd31ca4f451373fa8ed1351f48473a1c39633R5042

async def get_pubsub_message(self) -> PubSubMsg:
def try_get_pubsub_message(self) -> Optional[PubSubMsg]:

[acarbonetto]

remove?

[Yury-Fridlyand]

I think we need to log it through logger too.