add PR link to changelog

CHANGELOG.md

@@ -12,7 +12,7 @@ This project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.htm
 
 - Added support for providing `endpoint`, `pollingIntervalMs` and `initialSamplingRate` using environment variable `OTEL_TRACES_SAMPLER_ARG` in `go.opentelemetry.io/contrib/samples/jaegerremote`. (#6310)
 - Added support exporting logs via OTLP over gRPC in `go.opentelemetry.io/contrib/config`. (#6340)
-- Added support for configuring `Certificate` field when configuring OTLP exporters in `go.opentelemetry.io/contrib/config`. (#6376)
+- Added support for configuring `Certificate`, `ClientCertificate`, and `ClientKey` field when exporting OTLP over gRPC in `go.opentelemetry.io/contrib/config`. (#6376) (#6378)
 
 ### Changed
 
@@ -39,7 +39,7 @@ This project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.htm
   - Use `baggagecopy.NewLogProcessor` when configuring a Log Provider.
     - `NewLogProcessor` accepts a `Filter` function type that selects which baggage members are added to the log record.
 
-### Changed 
+### Changed
 
 - Transform raw (`slog.KindAny`) attribute values to matching `log.Value` types.
   For example, `[]string{"foo", "bar"}` attribute value is now transformed to `log.SliceValue(log.StringValue("foo"), log.StringValue("bar"))` instead of `log.String("[foo bar"])`. (#6254)