Fix Authorization Granted Events sample

[skdas20]

The sample under Authorization Granted Events does not compile, and the prose around it describes behaviour SpringAuthorizationEventPublisher does not have.

The sample. It calls a no-arg constructor, but the only one is SpringAuthorizationEventPublisher(ApplicationEventPublisher), and it calls setShouldPublishEvent, which is setShouldPublishResult(Predicate<AuthorizationResult>). The Kotlin version additionally destructures the lambda parameter as (result), refers to an undefined decision instead of the parameter, and uses bare return inside a lambda, none of which compile.

The prose. It says the publisher "only publishes authorization grants where ROLE_ADMIN was required", but the class javadoc states the opposite:

Because AuthorizationGrantedEvents typically require additional business logic to decide whether to publish, this implementation only publishes AuthorizationDeniedEvents.

and publishAuthorizationEvent bears that out — it only ever constructs an AuthorizationDeniedEvent; AuthorizationGrantedEvent is imported solely for that javadoc reference. So a predicate returning true for a granted result publishes an AuthorizationDeniedEvent carrying a granted AuthorizationResult, which is not what a reader following this section would expect.

I have taken the implementation as correct and fixed the documentation to match it, describing the predicate as selecting which denials are published. The default is (result) -> !result.isGranted(), so that reading seems consistent with the intended design.

If the team would rather SpringAuthorizationEventPublisher gain the ability to publish granted events, then this section is describing a feature request instead and the fix belongs in the class rather than the docs — happy to redo it that way.

Closes gh-19584