Fix incorrect changelog version format

Author: andrew-oc

Packages/com.unity.inputsystem/CHANGELOG.md

@@ -8,7 +8,7 @@ and this project adheres to [Semantic Versioning](http://semver.org/spec/v2.0.0.
 Due to package verification, the latest version below is the unpublished version and the date is meaningless.
 however, it has to be formatted properly to pass verification tests.
 
-## [2021-12-10]
+## [1.3.0] - 2021-12-10
 
 ### Changed