Update README.md

[skip ci]

Author: edizor

kotlin-testing/README.md

@@ -7,3 +7,4 @@ This module contains articles about testing in Kotlin
 - [Kotlin with Mockito](https://www.baeldung.com/kotlin/mockito)
 - [Writing Specifications with Kotlin and Spek](https://www.baeldung.com/kotlin/spek)
 - [MockK: A Mocking Library for Kotlin](https://www.baeldung.com/kotlin/mockk)
+- [Testing a Lambda Function With Mockito Kotlin](https://www.baeldung.com/kotlin/mockito-verify-lambda)