Creating a release

Prepare a GitHub release-draft x.x
Change version constants in src/Constants.php
Adjust the file UPGRADING.md with version specific information
Adjust the versions in SECURITY.md
Create CHANGELOG.md:
- Change .github_changelog_generator config accordingly to new release tag (increase future release)
- Run github-changelog-generator with github_changelog_generator --user kevinpapst --project kimai2 --max-issues 500 --since-tag 1.15.5
Edit the release-draft and add the “Full changelog” link + everything new from CHANGELOG.md
Push a release branch called release-x.x and merge it as last PR into master
Publish the release
Adjust Kimai website:
- Change version in file _config.yml and key kimai_v2_version
- Create a new version announcement post, including the release notes
Post a new issue at YunoHost tracker for Kimai
Post a new issue at Docker for Kimai
Reinstall the stable-demo and change tag version in install.sh