bump plotly.js to 2.5.1

Author: nicolaskruchten

CHANGELOG.md

@@ -9,6 +9,8 @@ This project adheres to [Semantic Versioning](http://semver.org/).
 
 ### Updated
   - The JSON serialization engines no longer sort their keys [#3380](https://github.com/plotly/plotly.py/issues/3380)
+  - Updated Plotly.js to from version 2.4.2 to version 2.5.1. See the [plotly.js CHANGELOG](https://github.com/plotly/plotly.js/blob/master/CHANGELOG.md#240----2021-08-27) for more information.
+
 
 ## [5.3.1] - 2021-08-31