Update README.md

[skip ci]

Author: edizor

scala-libraries-4/README.md

@@ -3,3 +3,4 @@
 - [Introduction to uTest](https://www.baeldung.com/scala/utest-intro)
 - [Introduction to scala-async](https://www.baeldung.com/scala/scala-async)
 - [Get the First N Rows of a Spark Dataframe](https://www.baeldung.com/scala/spark-dataframe-get-first-n-rows)
+- [Introduction to Skunk – Scala Driver for PostgreSQL](https://www.baeldung.com/scala/skunk-postgresql-driver)