v0.9.15: maintenance + bugfix release

[vobu]

That's it, that's the release scope 😃
Other than that, we have dropped Node v17 support both in CI and for the docker images, as v17 is not actively maintained anymore and not a LTS version of node.

(what happened to v0.9.14, you ask? Well, you should ask @dominikfeininger about that 🤣
But all in all, it was/is equivalent to v0.9.13)