Add changelog entry

Author: mihaeu

CHANGELOG.md

@@ -7,6 +7,10 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased]
 
+### Added
+
+-   Added config option `personalAccessToken` and environment variable `CONFLUENCE_PERSONAL_ACCESS_TOKEN` in order to support authentication using [personal access tokens](https://confluence.atlassian.com/enterprise/using-personal-access-tokens-1026032365.html). (solves [#26](https://github.com/mihaeu/cosmere/issues/26))
+
 ## [0.14.1] - 2021-08-25
 
 ### Fixed