Update changelog

Author: alanwest

src/OpenTelemetry/CHANGELOG.md

@@ -2,6 +2,10 @@
 
 ## Unreleased
 
+* The default resource provided by `ResourceBuilder.CreateDefault()` now
+  adds the `telemetry.sdk.*` attributes defined in the
+  [specification](https://github.com/open-telemetry/opentelemetry-specification/tree/12fcec1ff255b1535db75708e52a3a21f86f0fae/specification/resource/semantic_conventions#semantic-attributes-with-sdk-provided-default-value).
+  ([#4369](https://github.com/open-telemetry/opentelemetry-dotnet/pull/4369))
 * Fixed an issue with `HashCode` computations throwing exceptions on .NET
   Standard 2.1 targets.
   ([#4362](https://github.com/open-telemetry/opentelemetry-dotnet/pull/4362))