This is more complicated as you think. Greenbone is the maintainer and developer of this git software repository at GitHub. We are publishing releases of this software a .zip or .tag.gz archives. Additionally we provide container images, extensive docs on how to build our software from these archive files and docs for using the container images. That’s it. We do not package the software for any Linux distribution. Also we have no influence when or how our software is packaged. The integration into a Linux distribution like Kali is up to the packagers of this distribution. Therefore issues with the postgres database setup are completely out of our control on Kali and all other distributions.