Merge branch 'release/3.1.0' into develop

Author: ma4nn

CHANGELOG.md

@@ -4,6 +4,12 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](http://keepachangelog.com/)
 and this project adheres to [Semantic Versioning](http://semver.org/).
 
+## [3.1.0] - 2022-08-24
+### Changed
+- Upgraded DomPDF library to version 2
+- Upgraded other dependences
+- Raised minimum PHP version to 7
+
 ## [3.0.0] - 2021-06-01
 ### Changed
 - Refactored logic for pdf attachment files