[6.x] update changelog

Author: TBlindaruk

CHANGELOG-6.x.md

@@ -1,6 +1,12 @@
 # Release Notes for 6.x
 
-## [Unreleased](https://github.com/laravel/framework/compare/v6.20.8...6.x)
+## [Unreleased](https://github.com/laravel/framework/compare/v6.20.9...6.x)
+
+
+## [v6.20.9 (2021-01-05)](https://github.com/laravel/framework/compare/v6.20.8...v6.20.9)
+
+### Added
+- [Updated Illuminate\Database\DetectsLostConnections with new strings](https://github.com/laravel/framework/compare/v6.20.8...v6.20.9) 
 
 
 ## [v6.20.8 (2020-12-22)](https://github.com/laravel/framework/compare/v6.20.7...v6.20.8)