Update changelog

CHANGELOG.md

@@ -8,6 +8,12 @@ This project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.htm
 
 ## [Unreleased]
 
+## [1.16.0/0.39.0] 2023-05-18
+
+This release contains the first stable release of the OpenTelemetry Go [metric API].
+Our project stability guarantees now apply to the `go.opentelemetry.io/otel/metric` package.
+See our [versioning policy](VERSIONING.md) for more information about these stability guarantees.
+
 ### Added
 
 - The `go.opentelemetry.io/otel/semconv/v1.20.0` package.
@@ -2487,7 +2493,8 @@ It contains api and sdk for trace and meter.
 - CircleCI build CI manifest files.
 - CODEOWNERS file to track owners of this project.
 
-[Unreleased]: https://github.com/open-telemetry/opentelemetry-go/compare/v1.16.0-rc.1...HEAD
+[Unreleased]: https://github.com/open-telemetry/opentelemetry-go/compare/v1.16.0...HEAD
+[1.16.0/0.39.0]: https://github.com/open-telemetry/opentelemetry-go/releases/tag/v1.16.0
 [1.16.0-rc.1/0.39.0-rc.1]: https://github.com/open-telemetry/opentelemetry-go/releases/tag/v1.16.0-rc.1
 [1.15.1/0.38.1]: https://github.com/open-telemetry/opentelemetry-go/releases/tag/v1.15.1
 [1.15.0/0.38.0]: https://github.com/open-telemetry/opentelemetry-go/releases/tag/v1.15.0
@@ -2557,3 +2564,5 @@ It contains api and sdk for trace and meter.
 [Go 1.20]: https://go.dev/doc/go1.20
 [Go 1.19]: https://go.dev/doc/go1.19
 [Go 1.18]: https://go.dev/doc/go1.18
+
+[metric API]:https://pkg.go.dev/go.opentelemetry.io/otel/metric