Align MeterRegistryConfigurer's javadoc with its implementation

Closes gh-15017

spring-boot-project/spring-boot-actuator-autoconfigure/src/main/java/org/springframework/boot/actuate/autoconfigure/metrics/MeterRegistryConfigurer.java

@@ -30,9 +30,7 @@ import org.springframework.boot.util.LambdaSafe;
 /**
  * Configurer to apply {@link MeterRegistryCustomizer customizers}, {@link MeterFilter
  * filters}, {@link MeterBinder binders} and {@link Metrics#addRegistry global
- * registration} to {@link MeterRegistry meter registries}. This configurer intentionally
- * skips {@link CompositeMeterRegistry} with the assumptions that the registries it
- * contains are beans and will be customized directly.
+ * registration} to {@link MeterRegistry meter registries}.
  *
  * @author Jon Schneider
  * @author Phillip Webb
@@ -58,6 +56,9 @@ class MeterRegistryConfigurer {
 	}
 
 	void configure(MeterRegistry registry) {
+		if (registry instanceof CompositeMeterRegistry) {
+			return;
+		}
 		// Customizers must be applied before binders, as they may add custom
 		// tags or alter timer or summary configuration.
 		customize(registry);