chore: add changelog entry

Author: boekkooi-impossiblecloud

CHANGELOG.md

@@ -19,6 +19,7 @@ This project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.htm
 - Propagate non-retryable error messages to client in `go.opentelemetry.io/otel/exporters/otlp/otlplog/otlploghttp`. (#5929)
 - Propagate non-retryable error messages to client in `go.opentelemetry.io/otel/exporters/otlp/otlptrace/otlptracehttp`. (#5929)
 - Propagate non-retryable error messages to client in `go.opentelemetry.io/otel/exporters/otlp/otlpmetric/otlpmetrichttp`. (#5929)
+- Performance improvements for attribute value `AsStringSlice`, `AsFloat64Slice`, `AsInt64Slice`, `AsBoolSlice`. (#6011)
 
 ### Fixed