Add French translation of README.md (#718)

* Add French translation of README.md

* Update README.md

Co-authored-by: Stephen Celis <[email protected]>

Author: 2 people

README.md

@@ -434,6 +434,7 @@ If you want to discuss the Composable Architecture or have a question about how
 
 The following translations of this README have been contributed by members of the community:
 
+* [French](https://gist.github.com/nikitamounier/0e93eb832cf389db12f9a69da030a2dc)
 * [Korean](https://gist.github.com/pilgwon/ea05e2207ab68bdd1f49dff97b293b17)
 * [Indonesian](https://gist.github.com/wendyliga/792ea9ac5cc887f59de70a9e39cc7343)
 * [Italian](https://gist.github.com/Bellaposa/5114e6d4d55fdb1388e8186886d48958)