Add Kotlin support to PreFilter and PostFilter annotations

[call-me-baki]

Closes the following issue:

• 15093

Summary Adds support for Kotlin in DefaultMethodSecurityExpressionHandler.

It additionally updates the documentation (both javadoc and asciidoc) to reflect the current implementation details and usage.

Implementation details Attempts to mutate the state of either the Collection or the Map:

• if an UnsupportedOperationException is not thrown, returns the instance with its state mutated.
• if an UnsupportedOperationException is thrown, returns a new instance with the filtered state.

Tests The original Java test DefaultMethodSecurityExpressionHandlerTests has been left unchanged and acts as a regression test.

A new test DefaultMethodSecurityExpressionHandlerKotlinTests has been added to assert over the correct behavior when using Kotlin instead of Java.

[call-me-baki]

Thank you @jzheaux for the feedback! 🙏🏼

I've addressed the requested changes, would you please have a look again?

Regarding adding myself to JavaDoc's authors, I'm completely fine if we revert that commit should this change not warrant it.

[jzheaux]

Thanks for the updates, @call-me-baki! In preparation for merging, will you please do the following:

1. Run ./gradlew format && ./gradlew :spring-security-core:check and make any changes the output requires
2. Squash your commits into one
3. Ensure your commit message is brief and also contains Closes gh-15093, for example:

Add Kotlin support for Pre-PostFilter Annotations

Closes gh-15093

[call-me-baki]

Hey @jzheaux! Thanks for your support and guidance.

I ran ./gradlew format && ./gradlew :spring-security-core:check, there wasn't anything actionable. The commits have been squashed and I hope that the commit message is fitting.

Looking forward to contributing to Spring Security in the future!

[jzheaux]

Thanks again, @call-me-baki! This is now merged into main and will go out in the next milestone release. I also added a slight polish in aa9bf83c6d0be0c40e868e085dfd8e809afa4e91 to clarify variable names and align logging levels.