Move changelog entry to unreleased section.

Author: Karl-Krauth

Diff for: CHANGELOG.md

@@ -2,12 +2,13 @@
 All notable changes to this project will be documented in this file.
 This project adheres to [Semantic Versioning](http://semver.org/).
 
+## UNRELEASED
+ - Fixed two issues with px.imshow: [#4330] when facet_col is an earlier dimension than animation_frame for xarrays and [#4329] when facet_col has string coordinates in xarrays [#4331]
+
 ## [5.16.1] - 2023-08-16
 
 ### Fixed
 - Fixed issue with necessary columns from complex arguments dropped when interchanging dataframes [[#4324](https://github.com/plotly/plotly.py/pull/4324)]
-- Fixed issue with px.imshow failing when facet_col is an earlier dimension than animation_frame for xarrays [[#4330](https://github.com/plotly/plotly.py/issues/4330)]
-- Fixed issue with px.imshow failing when facet_col has string coordinates in xarrays [[#4329](https://github.com/plotly/plotly.py/issues/4329)]
 
 ## [5.16.0] - 2023-08-11