Merge pull request kbsali#280 from Art4/v1.x

Update CHANGELOG.md

Author: Art4

CHANGELOG.md

@@ -7,6 +7,10 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased](https://github.com/kbsali/php-redmine-api/compare/v1.8.0...master)
 
+### Fixed
+
+- `AbstractApi::get()` returns `null` on empty response body instead of `false` for BC reasons
+
 ## [v1.8.0](https://github.com/kbsali/php-redmine-api/compare/v1.7.0...v1.8.0) - 2021-04-19
 
 ### Added