Spring Fix javadoc reference to ThrowsAdvice

In the process of learning, I found a little flaw in Javadoc

Maybe we can change {@link org.springframework.aop.MethodBeforeAdvice} to {@link org.springframework.aop.ThrowsAdvice}

Comment From: pivotal-cla

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Comment From: pivotal-cla

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Comment From: snicoll

@aoyvx thank you for making your first contribution to Spring Framework.