Added deprecation removal to release notes
### Version 3.4.5 (TBA)
* Support for dockerizing Spring Boot applications. - [Pull Request 619](https://github.com/bmuschko/gradle-docker-plugin/pull/619)
+* Removed deprecated `ResponseHandler` - [Pull Request 624](https://github.com/bmuschko/gradle-docker-plugin/pull/624)
* Upgrade to Gradle Wrapper 4.9
### Version 3.4.4 (July 15, 2018)
