free-courses-en: add LUA course (#10606)

courses/free-courses-en.md

@@ -1170,6 +1170,7 @@
 
 * [Learn Lua in 15 Minutes](http://tylerneylon.com/a/learn-lua/) - Tyler Neylon (HTML)
 * [Lua Interactive Crash Course](https://web.archive.org/web/20201111225216/luatut.com/crash_course.html)
+* [Lua Programming Tutorials](https://www.youtube.com/playlist?list=PLYBJzqz8zpWavt37pA6NANJTGStIHpybU) - Steve's teacher
 * [Lua Tutorial](https://www.youtube.com/watch?v=iMacxZQMPXs) - Derek Banas