Adds link to Persian (Farsi) translation in progress.

README.md

@@ -48,6 +48,7 @@
 - [Thai](https://github.com/jwasham/coding-interview-university/issues/156)
 - [Greek](https://github.com/jwasham/coding-interview-university/issues/166)
 - [Malayalam](https://github.com/jwasham/coding-interview-university/issues/239)
+- [Persian - Farsi](https://github.com/jwasham/coding-interview-university/issues/186)
 
 </details>