add changelog entry

Author: moredip

CHANGELOG.md

@@ -40,6 +40,8 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
   ([#2792](https://github.com/open-telemetry/opentelemetry-python-contrib/pull/2792))
 - `opentelemetry-instrumentation-tornado` Handle http client exception and record exception info into span
   ([#2563](https://github.com/open-telemetry/opentelemetry-python-contrib/pull/2563))
+- `opentelemetry-instrumentation-sqlalchemy` Fixes engines from sqlalchemy.engine_from_config(...) not being fully instrumented
+  ([#2816](https://github.com/open-telemetry/opentelemetry-python-contrib/pull/2816))
 
 ## Version 1.26.0/0.47b0 (2024-07-23)