Spring Fix Kotlin example for filtering handler functions

The Kotlin code example at Filtering Handler Functions seems to be not equivalent to Java.

Suppose

The before filter that adds a custom request header is only applied to the two GET routes. The after filter that logs the response is applied to all routes, including the nested ones.

is correct, POST("/person", handler::createPerson) and after() should not be inside nest, if my understanding to RouterFunction is correct.

Comment From: sbrannen

This has been merged into main.

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