Improve release management

[shibumi]

I would like to do some improvements regarding release management. This involves several software supply chain security improvements:

1. Creating a changelog with every release
2. Creating a SBOM for every release (Software Bill of Materials)
3. Create signed releases with the chainguard stack

An example project for such a project can be found here: https://github.com/shibumi/secure-supply-chain-example

Would be nice if we manage to be SLSA compliant with our releases.