🥷 Add "Are we async yet?"

Author: dumindu

content/en/docs/a1.why-rust.md

@@ -45,3 +45,4 @@ Rust compiler observes the code **at compile-time** and helps to [**prevent many
   - [Are we game yet?](http://arewegameyet.com/)
   - [Are we learning yet?](http://www.arewelearningyet.com/)
   - [Are we GUI yet?](https://areweguiyet.com/)
+  - [Are we async yet?](https://areweasyncyet.rs/)