chore: indicate why this repository get's archived

[lukasholzer]

🎉 Thanks for submitting a pull request! 🎉

Summary

This is part of https://github.com/netlify/build/issues/4545. The moving PR is: https://github.com/netlify/build/pull/4584

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For us to review and ship your PR efficiently, please perform the following steps:

• [ ] Open a bug/issue before writing your code 🧑‍💻. This ensures we can discuss the changes and get feedback from everyone that should be involved. If you`re fixing a typo or something that`s on fire 🔥 (e.g. incident related), you can skip this step.
• [ ] Read the contribution guidelines 📖. This ensures your code follows our style guide and passes our tests.
• [ ] Update or add tests (if any source code was changed or added) 🧪
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A picture of a cute animal (not mandatory, but encouraged)

[conventional-commit-lint-gcf[bot]]

🤖 I detect that the PR title and the commit message differ and there's only one commit. To use the PR title for the commit history, you can use Github's automerge feature with squashing, or use automerge label. Good luck human!

-- conventional-commit-lint bot https://conventionalcommits.org/