Added Data Structure and Algorithm Course (#7492)

* Added Data Structure and Algorithm Course

* Update courses/free-courses-en.md

Co-authored-by: David Ordás <3125580+davorpa@users.noreply.github.com>

* lint: alphabetize

Co-authored-by: David Ordás <3125580+davorpa@users.noreply.github.com>

courses/free-courses-en.md

@@ -117,6 +117,7 @@
 * [Berkeley University CS 61B: Data Structures](http://datastructur.es/sp16/)
 * [Berkeley's CS 61B: Data Structures](https://archive.org/details/ucberkeley_webcast_QMV45tHCYNI)
 * [Complete C++ Placement DSA Course](https://www.youtube.com/playlist?list=PLDzeHZWIZsTryvtXdMr6rPh4IDexB5NIA) - CodeHelp - by Babbar
+* [Data Structure and Algorithm](https://www.youtube.com/playlist?list=PLLvKknWU7N4y_eGpQdg1Y-hORO7cxtoLU) - Lalit Vashistha
 * [Data Structures](https://www.youtube.com/playlist?list=PL2_aWCzGMAwI3W_JlcBbtYTwiQSsOTa6P) - mycodeschool
 * [Data Structures](https://stepik.org/course/579/syllabus) - Niema Moshiri, Liz Izhikevich (Stepik)
 * [Data Structures and Algorithms](https://youtube.com/playlist?list=PLBZBJbE_rGRV8D7XZ08LK6z-4zPoWzu5H) - CS Dojo