Kafka consumer LeaveGroup request to coordinator

Question

I have one interesting scenario. Seems like when there are no new topics to pick up (at least that's what I think is happening), my consumer suddenly shuts down.

I am using Kotlin + Spring Boot Kafka Producer and Consumer. My consumer is configured like this:

spring:
  profiles:
    active: ${SPRING_PROFILE:prod}
  cloud:
    stream:
      bindingRetryInterval: ${BINDING_RETRY_INTERVAL:0}
      default:
        contentType: application/*+avro
        group: my-app
        consumer:
          useNativeDecoding: false
          concurrency: ${CONSUMER_CONCURRENCY:3}
          maxAttempts: ${CONSUMER_MAX_ATTEMPTS:3}

      bindings:
        outbox:
          # Topic to consume from
          destination: my_outbox_topic
      kafka:
        bindings:
          outbox:
            consumer:
              enableDlq: ${ENABLE_DLQ:false}
        binder:
          brokers: ${BOOTSTRAP_SERVERS:localhost:9092}
          configuration.ssl.endpoint.identification.algorithm: ${SSL_ALGORITHM:}
          consumerProperties:
            schema.registry.url: ${SCHEMA_REGISTRY_URL:http://localhost:8081}
            key.deserializer: org.apache.kafka.common.serialization.StringDeserializer
            value.deserializer: io.confluent.kafka.serializers.KafkaAvroDeserializer
            specific.avro.reader: false

So I start the app, it consumes for a while and then I get these types of logs:

2021-09-28 12:57:38.113 INFO 4254 --- [container-0-C-1] o.a.k.c.c.internals.AbstractCoordinator : [Consumer clientId=consumer-2,
groupId=youscript-app] Member consumer-2-dc0e4115-6e9a-4a99-9d04-a3a2efb2c7b3 sending LeaveGroup request to coordinator __MASKES__:9094 (id: 2147483646 rack: null)
2021-09-28 12:57:38.113 INFO 4254 --- [container-0-C-1] o.a.k.clients.consumer.KafkaConsumer   : [Consumer clientId=consumer-2, groupId=my-app] Unsubscribed all topics or patterns and assigned partitions
2021-09-28 12:57:38.113 INFO 4254 --- [container-0-C-1] o.s.s.c.ThreadPoolTaskScheduler     : Shutting down ExecutorService
2021-09-28 12:57:38.120 INFO 4254 --- [container-1-C-1] o.a.k.c.c.internals.AbstractCoordinator : [Consumer clientId=consumer-3, groupId=my-app] Member consumer-3-701431a3-7cb9-4962-8f89-f2df41a176fd sending LeaveGroup request to coordinator __MASKED__:9094 (id: 2147483646 rack: null)
2021-09-28 12:57:38.120 INFO 4254 --- [container-1-C-1] o.a.k.clients.consumer.KafkaConsumer   : [Consumer clientId=consumer-3, groupId=my-app] Unsubscribed all topics or patterns and assigned partitions
2021-09-28 12:57:38.120 INFO 4254 --- [container-1-C-1] o.s.s.c.ThreadPoolTaskScheduler     : Shutting down ExecutorService
2021-09-28 12:57:38.189 INFO 4254 --- [container-1-C-1] essageListenerContainer$ListenerConsumer : my-app: Consumer stopped
2021-09-28 12:57:38.197 INFO 4254 --- [container-0-C-1] essageListenerContainer$ListenerConsumer : my-app: Consumer stopped