fix(docs): add Wayback Machine archive URL for Erlang chat app tutorial

Author: ferkans-amir

README.md

@@ -196,7 +196,7 @@ To get started, simply fork this repo. Please refer to [CONTRIBUTING.md](CONTRIB
 ## Erlang
 
 - [ChatBus : build your first multi-user chat room app with Erlang/OTP](https://medium.com/@kansi/chatbus-build-your-first-multi-user-chat-room-app-with-erlang-otp-b55f72064901)
-- [Making a Chat App with Erlang, Rebar, Cowboy and Bullet](https://marianoguerra.org/posts/making-a-chat-app-with-erlang-rebar-cowboy-and-bullet/)
+- [Making a Chat App with Erlang, Rebar, Cowboy and Bullet](https://web.archive.org/web/20190825111509/http://marianoguerra.org/posts/making-a-chat-app-with-erlang-rebar-cowboy-and-bullet/)
 
 ## F#: