Added free interactive tutorial. (#5341)

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

@@ -128,6 +128,7 @@
 ### Go
 
 * [Go Koans](https://github.com/cdarwin/go-koans)
+* [Start using Go](https://docs.microsoft.com/en-us/learn/paths/go-first-steps/) - Microsoft
 * [The Go Tutorial](http://tour.golang.org)