Update README.md

Author: rcalago

core-kotlin-modules/core-kotlin-datastructures-2/README.md

@@ -5,3 +5,4 @@ This module contains articles about data structures in Kotlin
 ### Relevant articles:
 - [Matrix Addition and Multiplication in Kotlin](https://www.baeldung.com/kotlin/matrix-addition-multiplication)
 - [Insert an Element at a Given Position Into an Array in Kotlin](https://www.baeldung.com/kotlin/array-insert-item-chosen-index)
+- [Check if an Enum Value Contains a Given String in Kotlin](https://www.baeldung.com/kotlin/enum-contains-string)