Update CHANGELOG

Signed-off-by: Atri Sharma <atri.jiit@gmail.com>

Author: atris

CHANGELOG.md

@@ -8,6 +8,7 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 - [Feature Request] Enhance Terms lookup query to support query clause instead of docId ([#18195](https://github.com/opensearch-project/OpenSearch/issues/18195))
 - Add hierarchical routing processors for ingest and search pipelines ([#18826](https://github.com/opensearch-project/OpenSearch/pull/18826))
 - Add ACL-aware routing processors for ingest and search pipelines ([#18834](https://github.com/opensearch-project/OpenSearch/pull/18834))
+- Add temporal routing processors for time-based document routing ([#18920](https://github.com/opensearch-project/OpenSearch/issues/18920))
 - Add support for Warm Indices Write Block on Flood Watermark breach ([#18375](https://github.com/opensearch-project/OpenSearch/pull/18375))
 - FS stats for warm nodes based on addressable space ([#18767](https://github.com/opensearch-project/OpenSearch/pull/18767))
 - Add support for custom index name resolver from cluster plugin ([#18593](https://github.com/opensearch-project/OpenSearch/pull/18593))