remove broken video link

src/data/roadmaps/flutter/content/106-design-principles/101-design-patterns.md

@@ -17,5 +17,4 @@ Learn more from the following links:
 
 - [Flutter - Design](https://dart.dev/guides/language/effective-dart/design)
 - [Design Patterns Explained in 10 Minutes](https://www.youtube.com/watch?v=tv-_1er1mWI)
-- [Cookbook Designs in Flutter](https://docs.flutter.dev/cookbook/design)
-- [Flutter Design Patterns](https://www.youtube.com/watch?v=sk5hwzfndqs&list=pllzmawv2ytgb-1ldoo-9vctgre-1dywkp&index=1)
+- [Cookbook Designs in Flutter](https://docs.flutter.dev/cookbook/design)