GH-1817: Fix typo; revert unintended sample changes

Author: garyrussell

samples/sample-04/src/main/java/com/example/Application.java

@@ -45,7 +45,7 @@ public static void main(String[] args) {
 	}
 
 	@RetryableTopic(attempts = "5", backoff = @Backoff(delay = 2_000, maxDelay = 10_000, multiplier = 2))
-	@KafkaListener(id = "fooGroup", topics = "topic4", clientIdPrefix = "test")
+	@KafkaListener(id = "fooGroup", topics = "topic4")
 	public void listen(String in, @Header(KafkaHeaders.RECEIVED_TOPIC) String topic,
 			@Header(KafkaHeaders.OFFSET) long offset) {
 

samples/sample-04/src/main/resources/application.properties

@@ -1,4 +1,3 @@
 logging.level.root=off
-logging.level.org.apache.kafka=info
 logging.level.com.example=info
 #logging.level.org.springframework.kafka=error

spring-kafka-docs/src/main/asciidoc/kafka.adoc

@@ -1868,7 +1868,7 @@ void listen(Object in, @Header(KafkaHeaders.RECORD_METADATA) ConsumerRecordMetad
 
 Starting with version 2.7.2, you can now programmatically modify annotation attributes before the container is created.
 To do so, add one or more `KafkaListenerAnnotationBeanPostProcessor.AnnotationEnhancer` to the application context.
-`AnnotationEnhancer` is a `BiFunction<Map<String, Object>, AnnotatedElement, Map<String, Object>` and must return a a map of attributes.
+`AnnotationEnhancer` is a `BiFunction<Map<String, Object>, AnnotatedElement, Map<String, Object>` and must return a map of attributes.
 The attribute values can contain SpEL and/or property placeholders; the enhancer is called before any resolution is performed.
 If more than one enhancer is present, and they implement `Ordered`, they will be invoked in order.