[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/v6.20.33...6.x)
+## [Unreleased](https://github.com/laravel/framework/compare/v6.20.34...6.x)
+
+
+## [v6.20.34 (2021-09-07)](https://github.com/laravel/framework/compare/v6.20.33...v6.20.34)
+
+### Fixed
+- Silence validator date parse warnings ([#38670](https://github.com/laravel/framework/pull/38670))
 
 
 ## [v6.20.33 (2021-08-31)](https://github.com/laravel/framework/compare/v6.20.32...v6.20.33)