Update changelog

CHANGELOG.md

 
+<a name="v3.39.1"></a>
+## [v3.39.1] - 2023-04-03
+### Bug Fixes
+- this[attributeObserverSymbol] = {}; should defined before
+
+
 <a name="v3.39.0"></a>
 ## [v3.39.0] - 2023-04-03
 ### Add Features
@@ -551,6 +557,7 @@
 <a name="1.8.0"></a>
 ## 1.8.0 - 2021-08-15
 
+[v3.39.1]: https://gitlab.schukai.com/oss/libraries/javascript/monster/compare/v3.39.0...v3.39.1
 [v3.39.0]: https://gitlab.schukai.com/oss/libraries/javascript/monster/compare/v3.38.1...v3.39.0
 [v3.38.1]: https://gitlab.schukai.com/oss/libraries/javascript/monster/compare/v3.38.0...v3.38.1
 [v3.38.0]: https://gitlab.schukai.com/oss/libraries/javascript/monster/compare/v3.37.0...v3.38.0