Remove Stray JavaDoc Statement

As of the 5.2 release, a separate registrar bean was no longer necessary

Closes gh-15425

oauth2/oauth2-resource-server/src/main/java/org/springframework/security/oauth2/server/resource/web/reactive/function/client/ServletBearerExchangeFilterFunction.java

@@ -50,11 +50,6 @@
  * To locate the bearer token, this looks in the Reactor {@link Context} for a key of type
  * {@link Authentication}.
  *
- * Registering
- * {@see org.springframework.security.config.annotation.web.configuration.OAuth2ResourceServerConfiguration.OAuth2ResourceServerWebFluxSecurityConfiguration.BearerRequestContextSubscriberRegistrar},
- * as a {@code @Bean} will take care of this automatically, but certainly an application
- * can supply a {@link Context} of its own to override.
- *
  * @author Josh Cummings
  * @since 5.2
  */