[skip ci] updated release notes

docs/releases/v2.3.0.md

@@ -12,6 +12,7 @@
 - tweaked mesh loading strategies. Now it will wait for all image chunks to be loaded before loading any meshes
 - showing contributors to a regional feature/dataset if publications are not available
 - added the ability to customize preview origin dataset to labels other to `View probability map`
+- **experimental** : previewing of curated regional features: iEEG coordinates
 
 ## Bugfixes: