update changelog

changelog.md

@@ -2,6 +2,9 @@
 
 All notable changes to this project will be documented in this file.
 
+## [0.53] - 2023-06-21
+- Add banner explaining difference between average/mean for >48h time ranges
+
 ## [0.52] - 2023-04-17
 - Changed HTTP requests to reuse TCP connections to improve provisioning time
 - Changed Jinja template code to cache templates on startup