Update free-courses-en.md (#10917)

* Update free-courses-en.md

added new link for data structures and algorithm course

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* Update free-courses-en.md

* Update free-courses-en.md

Coreection in Title

* Update free-courses-en.md

removed duplicates

courses/free-courses-en.md

@@ -170,6 +170,7 @@
 * [Dynamic Programming](https://www.youtube.com/playlist?list=PLMCXHnjXnTnto1pZVvH7rbZ9W5neZ7Yhc) - Gaurav Sen
 * [Dynamic Programming](https://www.youtube.com/playlist?list=PLDV1Zeh2NRsAsbafOroUBnNV8fhZa7P4u) - WilliamFiset
 * [Dynamic Programming Playlist \| Interview Questions \| Recursion \| Tabulation \| Striver \| C++ \| Java \| DSA \| Placements](https://www.youtube.com/playlist?list=PLgUwDviBIf0qUlt5H_kiKYaNSqJ81PMMY) - take U forward
+* [ECS 36C: Data Structures, Algorithms, and Programming](https://lupteach.gitlab.io/courses/ucd-ecs36c/online/) - Joël Porquet-Lupine
 * [Graph Series by Striver \| C++ \| Java \| Interview Centric \| Algorithms \| Problems](https://www.youtube.com/playlist?list=PLgUwDviBIf0oE3gA41TKO2H5bHpPd7fzn) - take U forward
 * [Graph Theory playlist](https://youtube.com/playlist?list=PLDV1Zeh2NRsDGO4--qE8yH72HFL1Km93P) - WilliamFiset
 * [IIT Bombay Foundation of Data Structures (CS213.1x)](https://courses.edx.org/courses/course-v1:IITBombayX+CS213.1x+1T2017/course/)