add gulp.js resource to ar courses (#6906)

* add gulp.js resource to ar courses

* fix alphabetical order

Author: AhmedOsamaMath

Diff for: courses/free-courses-ar.md

@@ -210,6 +210,7 @@
 
 #### Gulp.js
 
+* [Automatic Your Work With Gulpjs](https://www.youtube.com/playlist?list=PLDoPjvoNmBAxyli7mXgNBhkRB-zgSHvL8) - Elzero Web School
 * [Basic of Gulp.js‏](https://www.youtube.com/playlist?list=PLfDx4cQoUNOaj10GLKu2YAcDQAMRvUgp0) - Algorithm Academy
 * [Gulp.js - Workshop‏](https://www.youtube.com/playlist?list=PLfDx4cQoUNOYXLQlBhKkc2bYIczytBc73) - Algorithm Academy