add CHANGELOG entry

Author: ned2

CHANGELOG.md

@@ -6,6 +6,7 @@ This project adheres to [Semantic Versioning](http://semver.org/).
 
 ### Fixed
 - Repair crash on Matplotlib 3.8 related to get_offset_position [[#4372](https://github.com/plotly/plotly.py/pull/4372)],
+- Handle deprecation of `pandas.Series.dt.to_pydatetime()` calls and suppress the `FutureWarning` they currently emit. [[#4379](https://github.com/plotly/plotly.py/pull/4379)]
 
 ## [5.17.0] - 2023-09-15