cli: update changelog with bare detection

Signed-off-by: Javi Fontan <jfontan@gmail.com>

Author: jfontan

CHANGELOG.md

@@ -6,6 +6,8 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased]
 
+- git libraries bare or non bare format is automatically detected ([#897](https://github.com/src-d/gitbase/pull/897))
+
 ## [0.22.0-beta1] - 2019-06-20
 
 ### Added