Update BraveAutoConfiguration.java (#14631)

The bean 'correlationFieldsCorrelationScopeCustomizer', defined in class path resource [org/apache/dubbo/spring/boot/observability/autoconfigure/brave/BraveAutoConfiguration$BraveBaggageConfiguration.class], could not be registered. A bean with that name has already been defined in class path resource [org/springframework/boot/actuate/autoconfigure/tracing/BravePropagationConfigurations$PropagationWithBaggage.class] and overriding is disabled.

Author: he-jialin2

dubbo-spring-boot/dubbo-spring-boot-starters/observability/autoconfigure/src/main/java/org/apache/dubbo/spring/boot/observability/autoconfigure/brave/BraveAutoConfiguration.java

@@ -272,6 +272,7 @@ brave.baggage.CorrelationScopeDecorator.Builder mdcCorrelationScopeDecoratorBuil
                 prefix = ObservabilityUtils.DUBBO_TRACING_BAGGAGE_CORRELATION,
                 name = "enabled",
                 matchIfMissing = true)
+        @ConditionalOnMissingBean
         brave.baggage.CorrelationScopeCustomizer correlationFieldsCorrelationScopeCustomizer() {
             return (builder) -> {
                 List<String> correlationFields = this.dubboConfigProperties