update changelog

Author: freesig

CHANGELOG-UNRELEASED.md

@@ -5,14 +5,15 @@ This project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.htm
 {{ version-heading }}
 
 ### Added
-
+- Adds tokio tracing to sim2h_server. [Description](https://holo.hackmd.io/@c5lIpp4ET0OJJnDT3gzilA/SyRm2YoEU). Also check `sim2h_server --help` for usage instructions.
 - Adds the notion of a manager to trycp_server so that we can dynamically manage pools of available nodes for test runs in final-exam  [PR#2123](https://github.com/holochain/holochain-rust/pull/2123)
 
 ### Changed
-
+- new_relic is behind a feature flag `new-relic`.
 ### Deprecated
 
 ### Removed
+- Older rust-tracing traces.
 
 ### Fixed