title: KafkaBindingRebalanceListener Bean not autowired with Multi-binder
body: <p>There is another post about a similar issue. The accepted answer works well with a single top-level binder. But I don't have luck with multi-binder. Not sure I mess up something or this technique only supports a single top-level binder.</p>
  <p><strong>Working YAML (only one top-level binder):</strong></p>
  <pre><code>spring:
    cloud:
      function:
        definition: consume;
      stream:
        function:
          bindings:
            consume-in-0: input
        bindings:
          input:
            destination: students
            group: groupA
        kafka:
          binder:
            brokers: 192.168.86.23:9092
  </code></pre>
  <p><strong>Broken YAML (multi-binder structure):</strong></p>
  <pre><code>spring:
    cloud:
      function:
        definition: consume;
      stream:
        function:
          bindings:
            consume-in-0: input
        bindings:
          input:
            destination: students
            group: groupA
            binder: kafkaBinder
        binders:
          kafkaBinder:
            type: kafka
            environment:
              spring:
                cloud:
                  stream:
                    kafka:
                      binder:
                        brokers: 192.168.86.23:9092
  </code></pre>
  <p><strong>SpringBootApplication:</strong></p>
  <pre><code>@SpringBootApplication
  public class Application {
  
      public static void main(String[] args) {
          SpringApplication.run(Application.class, args);
      }
  
      @Bean
      KafkaBindingRebalanceListener rebal() {
          return new KafkaBindingRebalanceListener() {
  
              @Override
              public void onPartitionsAssigned(String bindingName, Consumer&lt;?, ?&gt; consumer,
                                               Collection&lt;TopicPartition&gt; partitions, boolean initial) {
                  System.out.println(bindingName + &quot; assignments: &quot; + partitions + &quot;, initial call :&quot; + initial);
              }
  
          };
      }
  }
  </code></pre>
  <p>Another post: <em><a href="https://stackoverflow.com/questions/63157778/kafkabindingrebalancelistener-bean-not-autowired-by-kafkamessagechannelbinder-be">KafkaBindingRebalanceListener Bean not autowired by KafkaMessageChannelBinder Bean</a></em></p>