DSA course added - fixed, resolve #8288 (#8369)

Data Structures and Algorithms course added in Competitive Programming section.
Update free-courses-bn.md file

courses/free-courses-bn.md

@@ -63,6 +63,7 @@
 ### Competitive Programming
 
 * [Competitive Programming Course in Bengali](https://www.youtube.com/channel/UCozCCU3b1HmcmCf2gLN_7HA/videos) - Bangladesh IOI team
+* [Data Structures and Algorithms in Bangla](https://www.youtube.com/playlist?list=PLym69wpbTIIEOesltWGUsVnY9HDWbJit_) - Tamim Shahriar
 
 
 ### Dart