Adding one format fix

Author: shuningc

util/opentelemetry-util-genai/CHANGELOG.md

@@ -43,8 +43,8 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
   ([https://github.com/open-telemetry/opentelemetry-python-contrib/pull/3795](#3795))
 - Make inputs / outputs / system instructions optional params to `on_completion`,
   ([https://github.com/open-telemetry/opentelemetry-python-contrib/pull/3802](#3802)).
-  - Use a SHA256 hash of the system instructions as it's upload filename, and check
-    if the file exists before re-uploading it, ([https://github.com/open-telemetry/opentelemetry-python-contrib/pull/3814](#3814)).
+- Use a SHA256 hash of the system instructions as it's upload filename, and check
+  if the file exists before re-uploading it, ([https://github.com/open-telemetry/opentelemetry-python-contrib/pull/3814](#3814)).
 
 ## Version 0.1b0 (2025-09-25)