[chore]: Bump go.opentelemetry.io/otel/exporters/otlp/otlptrace/otlptracegrpc

Bumps [go.opentelemetry.io/otel/exporters/otlp/otlptrace/otlptracegrpc](https://github.com/open-telemetry/opentelemetry-go) from 1.34.0 to 1.35.0.
- [Release notes](https://github.com/open-telemetry/opentelemetry-go/releases)
- [Changelog](https://github.com/open-telemetry/opentelemetry-go/blob/main/CHANGELOG.md)
- [Commits](https://github.com/open-telemetry/opentelemetry-go/compare/v1.34.0...v1.35.0)

---
updated-dependencies:
- dependency-name: go.opentelemetry.io/otel/exporters/otlp/otlptrace/otlptracegrpc
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <support@github.com>

vendor/github.com/grpc-ecosystem/grpc-gateway/v2/runtime/handler.go

@@ -196,7 +196,7 @@ func ForwardResponseMessage(ctx context.Context, mux *ServeMux, marshaler Marsha
 		return
 	}
 
-	if !doForwardTrailers {
+	if !doForwardTrailers && mux.writeContentLength {
 		w.Header().Set("Content-Length", strconv.Itoa(len(buf)))
 	}