Add README link to learning resources (#34751)

Author: logankilpatrick

README.md

@@ -47,6 +47,7 @@ helpful to start contributing to the Julia codebase.
 - [**StackOverflow**](https://stackoverflow.com/questions/tagged/julia-lang)
 - [**Twitter**](https://twitter.com/JuliaLanguage)
 - [**Meetup**](https://julia.meetup.com/)
+- [**Learning resources**](https://julialang.org/learning/)
 
 ## Binary Installation