Add LearnScala.org to Scala resources (#12926)

* Add LearnScala.org to Scala resources

Added interactive Scala tutorial link.

* Fix link formatting for LearnScala.org

* Update free-courses-en.md

* Add LearnScala.org to Scala tutorials list

Author: Muditapandey26

more/free-programming-interactive-tutorials-en.md

@@ -455,6 +455,7 @@
 ### Scala
 
 * [A Tour of Scala - an interactive scala tutorial](https://scalatutorials.com/tour/)
+* [LearnScala.org](https://www.learnscala.org) - Interactive Scala Tutorial
 * [Scala Exercises](https://www.scala-exercises.org)