Add info about new release 3.9.2

Author: Smolevich

CHANGELOG.md

@@ -3,6 +3,14 @@ All notable changes to this project will be documented in this file.
 
 ## [Unreleased]
 
+## [3.9.2] - 2022-09-01
+
+### Addded 
+- Add single word name mutators https://github.com/jenssegers/laravel-mongodb/pull/2438 by [@RosemaryOrchard](https://github.com/RosemaryOrchard)
+
+### Fixed
+- Fix stringable sort https://github.com/jenssegers/laravel-mongodb/pull/2420 by [@apeisa](https://github.com/apeisa)
+
 ## [3.9.1] - 2022-03-11
 
 ### Added