Update BraveAutoConfiguration.java A bean with that name has already been defined

[he-jialin]

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.

What is the purpose of the change

According to dubbo3 design specifications, spring.main.allow-bean-definition-overriding=true should not be set as the default, so this problem needs to be fixed.

#14628

Brief changelog

Add the annotation @ConditionalOnMissingBean to determine whether the bean needs to be injected

Verifying this change

Checklist

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