Add The Odin Project as a resource in learning to code

The Odin Project is a full-stack curriculum that is fee and open source. 

Signed-off-by: Golam <[email protected]>

Author: golam71

collections/learn-to-code/index.md

@@ -38,6 +38,7 @@ items:
  - Hexlet/hexletguides.github.io
  - aykutkardas/regexlearn.com
  - olexale/flutter_roadmap
+ - TheOdinProject/curriculum
 
 display_name: Learn to Code
 created_by: alysonla