Add Kotlin friendly assertInstanceOf assertions

[bjmi]

Resolves #3353

Overview

Add Kotlin specific buddies for assertInstanceOf(..)

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Definition of Done

• There are no TODOs left in the code
• Method preconditions are checked and documented in the method's Javadoc
• Coding conventions (e.g. for logging) have been followed
• Change is covered by automated tests including corner cases, errors, and exception handling
• Public API has Javadoc and @API annotations
• Change is documented in the User Guide and Release Notes

[pixeebot]

This PR is from a forked repository. After this PR is merged into the default branch, pixeebot will provide suggestions via the Continuous Improvement campaign.

[marcphilipp]

@bjmi Thanks you your contribution! 👍