update version and changelog for 1.7.2 release

Author: awaelchli

src/pytorch_lightning/CHANGELOG.md

@@ -4,6 +4,13 @@ All notable changes to this project will be documented in this file.
 
 The format is based on [Keep a Changelog](http://keepachangelog.com/en/1.0.0/).
 
+## [1.7.2] - 2022-08-16
+
+### Fixed
+
+-
+
+
 ## [1.7.1] - 2022-08-09
 
 ### Fixed

src/pytorch_lightning/__version__.py

@@ -1 +1 @@
-version = "1.7.1"
+version = "1.7.2"