docs: add bn via @lingodotdev

Author: maxprilutskiy

packages/cli/README.md

@@ -172,5 +172,6 @@ Want to contribute? Create a pull request!
 - [Italian](/readme/it.md)
 - [Arabic](/readme/ar.md)
 - [Hindi](/readme/hi.md)
+- [Bengali](/readme/bn.md)
 
 Don't see your language? Just add a new language code to the [`i18n.json`](./i18n.json) file and open a PR.