Removing dead course (#5187)

free-courses-en.md

@@ -37,7 +37,6 @@
   * [React](#react)
   * [React Native](#react-native)
   * [Redux](#redux)
-  * [Sails.js](#sailsjs)
   * [Vue.js](#vuejs)
 * [Kotlin](#kotlin)
 * [Kubernetes](#kubernetes)
@@ -454,11 +453,6 @@
 * [Learn Redux](https://learnredux.com) - Wes Bos (email address *requested*)
 
 
-#### Sails.Js
-
-* [Develop web apps in free-programming-playgrounds.md.js and Sails.js](https://courses.platzi.com/courses/develop-apps-sails-js/)
-
-
 #### Vue.js
 
 * [Internationalization with vue-i18n](https://vueschool.io/courses/internationalization-with-vue-i18n)