Update CHANGELOG.md with fix of removed styles

Author: magjac

CHANGELOG.md

@@ -10,6 +10,9 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 * New option *useSharedWorker* that enables the use of a [shared web worker](https://developer.mozilla.org/en-US/docs/Web/API/SharedWorker). The default is still to use a [dedicated web worker](https://developer.mozilla.org/en-US/docs/Web/API/Worker).
 * New method [*graphviz*.**destroy**()](README.md#graphviz_destroy) to remove the Graphviz render from the element it was created on and release any resources it is holding.
 
+### Fixed
+* Styles added with the attributer are removed after transition #159
+
 ## [3.0.6]
 
 ### Changed