Update CHANGELOG.md

Author: crpietschmann

CHANGELOG.md

@@ -5,10 +5,12 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.1.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
-## vNext
+## v2.1.3
 
 Add:
 
+- Added `IBatchEmbeddingsGenerator` and `.AddTextsAsync` to support batch adding of texts to database.
+- Added OpenAI support for `IBatchEmbeddingsGenerator`
 - Added `IVectorTextResultItem.Similarity` and marked `IVectorTextResultItem.VectorComparison` obsolete. `VectorComparison` will be removed in the future.
 - Added more comment metadata to code