Add entry to changelog

CHANGELOG.md

@@ -49,6 +49,7 @@ Types of changes
 - CI scripts are improved to simplfy usage !49
 - Simplify build and usage on docker containers !49
 - Drastically reduce size of final docker container !49
+- Improve performance on cases with no interaction between all species !53
 ### Removed
 - Automatic flux between compartment components with same name !30
 - Jacobian operator is managed by the stepper instead of the model !39