Prepare next dev iteration

Update version and changelog.

Signed-off-by: zapbot <12745184+zapbot@users.noreply.github.com>

Author: zapbot

CHANGELOG.md

@@ -3,6 +3,9 @@ All notable changes to this add-on will be documented in this file.
 
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/).
 
+## [Unreleased]
+
+
 ## [12] - 2021-10-07
 ### Added
 - authentication/OfflineTokenRefresh.js - refresh oauth2 offline tokens
@@ -140,6 +143,7 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/).
 
 - First packaged version
 
+[Unreleased]: https://github.com/zaproxy/community-scripts/compare/v12...HEAD
 [12]: https://github.com/zaproxy/community-scripts/compare/v11...v12
 [11]: https://github.com/zaproxy/community-scripts/compare/v10...v11
 [10]: https://github.com/zaproxy/community-scripts/compare/v9...v10

gradle.properties

@@ -1,2 +1,2 @@
-version=12
-release=true
+version=13
+release=false