Fix version in CHANGELOG (#36)

Author: remicollet

CHANGELOG.md

@@ -4,7 +4,7 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
-## [3.7.6] - 2020-09-25
+## [3.8.0] - 2020-09-25
 
 ### Added
 - Rearrangement of equal items for non-homogeneous arrays with `JsonDiff::REARRANGE_ARRAYS` option.