Update CHANGELOG.md

Author: jbern0rd

CHANGELOG.md

@@ -5,10 +5,12 @@ All notable changes to this project will be documented in this file.
 ## [[NEXT]](https://github.com/iExecBlockchainComputing/iexec-result-proxy/releases/tag/vNEXT) 2023
 
 ### New Features
+* Enable Prometheus actuator. (#84)
 ### Bug Fixes
 * Fix link in changelog. (#83)
 ### Quality
 ### Dependency Upgrades
+* Upgrade to `expiringmap` 0.5.10. (#84)
 
 ## [[8.0.0]](https://github.com/iExecBlockchainComputing/iexec-result-proxy/releases/tag/v8.0.0) 2023-03-03