[Search] Mark version 11.4.0-beta.5 in release (Azure#25154)

* Mark version 11.4.0-beta.5 in release

* Update Changelog with semantic search changes

Author: Mohit-Chakraborty

sdk/search/Azure.Search.Documents/CHANGELOG.md

@@ -1,17 +1,14 @@
 # Release History
 
-## 11.4.0-beta.5 (Unreleased)
+## 11.4.0-beta.5 (2021-11-09)
 
 ### Features Added
+- Added support for [Semantic Search](https://docs.microsoft.com/azure/search/semantic-search-overview). `SearchOptions` now support specifying `SemanticSettings` to influence the search behavior.
 
 ### Breaking Changes
 - Renamed `IndexerStateHighWaterMark` to `IndexerChangeTrackingState`.
 - Renamed the property `HighWaterMark` to `ChangeTrackingState` in `IndexerState`.
 
-### Bugs Fixed
-
-### Other Changes
-
 ## 11.4.0-beta.4 (2021-10-05)
 
 ### Features Added