docs(core): document the release process

[IvoGoman]

Description

This introduces the description for the release process of Greenhouse. It follows a Release Flow-style approach where development and bug fixes are done on the main branch. In case of a release a new release branch will be created. Based on tags on the release branch, GitHub action are triggered to create a Draft Release including changelog and assets and upload the tagged Helm Chart and Container images.

Bugfixes will be done on the main branch and cherry-picked to the release branch based on PR comments.

What type of PR is this? (check all applicable)

• 🍕 Feature
• 🐛 Bug Fix
• 📝 Documentation Update
• 🎨 Style
• 🧑‍💻 Code Refactor
• 🔥 Performance Improvements
• ✅ Test
• 🤖 Build
• 🔁 CI
• 📦 Chore (Release)
• ⏩ Revert

Related Tickets & Documents

• Related PRs: feat(actions): enforce semantic pr title #675
• Related Issues: [FEAT] Changelog generation from commit messages #594

Added tests?

• 👍 yes
• 🙅 no, because they aren't needed
• 🙋 no, because I need help
• Separate ticket for tests # (issue/pr)

Please describe the tests that you ran to verify your changes. Provide instructions so we can reproduce. Please also list any relevant details for your test configuration

Added to documentation?

• 📜 README.md
• 🤝 Documentation pages updated
• 🙅 no documentation needed
• (if applicable) generated OpenAPI docs for CRD changes

Checklist

• My code follows the style guidelines of this project
• I have performed a self-review of my code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• My changes generate no new warnings
• I have added tests that prove my fix is effective or that my feature works
• New and existing unit tests pass locally with my changes

[uwe-mayer]

💯

straight forward!