Add Other Online Resources section

Author: adpi2

online-courses.md

@@ -42,13 +42,15 @@ For more on Scala Center's online courses, visit [this page](https://docs.scala-
 [Rock the JVM](https://rockthejvm.com) is a learning platform with free and premium courses on the Scala language, Akka, Cats Effect, ZIO, Apache Spark and other tools in the Scala ecosystem.
 It also has hundreds of [free video tutorials](https://youtube.com/rockthejvm) and [articles](https://blog.rockthejvm.com) on a variety of Scala-related topics.
 
-## Scala Exercises
+## Other Online Resources
+
+### Scala Exercises
 
 [Scala Exercises](https://www.scala-exercises.org/) is a series of lessons and exercises created by [47 Degrees](https://www.47deg.com/). It's a great way to get a brief introduction to Scala while testing your knowledge along the way.
 
 [Tour of Scala](https://tourofscala.com) gives you an introduction to Scala, step by step, from beginner to expert.
 
-## Dr. Mark C Lewis's lectures from Trinity University
+### Dr. Mark C Lewis's lectures from Trinity University
 
 [Dr. Mark C Lewis](https://www.cs.trinity.edu/~mlewis/) from Trinity University, San Antonio, TX, teaches programming courses using the Scala language. Course videos are available in YouTube for free. Some courses below.
 
@@ -57,14 +59,14 @@ It also has hundreds of [free video tutorials](https://youtube.com/rockthejvm) a
 
 You can visit his [YouTube channel](https://www.youtube.com/user/DrMarkCLewis/featured) for more videos.
 
-## Scala Learning Community
+### Scala Learning Community
 [Scala Learning Community on Discord](http://sca.la/learning-community), a growing online community connecting learners with online resources to learn Scala together.
 
-## allaboutscala
+### allaboutscala
 [allaboutscala](https://allaboutscala.com/) provides detailed tutorials for beginners.
 
-## DevInsideYou
+### DevInsideYou
 [DevInsideYou](https://youtube.com/devinsideyou) is a YouTube channel with hundreds of hours of free Scala content.
 
-## Visual Scala Reference
+### Visual Scala Reference
 [Visual Scala Reference](https://superruzafa.github.io/visual-scala-reference/), a guide to visually learn about Scala concepts and functions.