Update CHANGELOG.md

Author: chrisjsewell

CHANGELOG.md

@@ -2,7 +2,8 @@
 
 ## 0.5.0 - 2025-08-11
 
-Drop Python 3.9, which is EoL next month <https://devguide.python.org/versions> and allow for the, soon to be released, markdown-it-py v4.
+- ⬆️ Drop Python 3.9, which is EoL next month <https://devguide.python.org/versions> and allow for the, soon to be released, markdown-it-py v4.
+- ✨ NEW: Add plugin & tests to render subscripts, thanks to @miteshashar
 
 ## 0.4.2 - 2024-09-09