Docker image to build/test extensions?

I noticed that this template checks out a copy of the duckdb source as a submodule, builds it along with the extension to execute tests etc. While there may be legit reasons because of which things are set up this way, I'm curious to see if anyone has a docker image with a pre-built duckdb that allows me to mount my extension as a volume to build and test.

Benefits:

* Hopefully faster build times. Even with ninja/ccache, I was running into OOMs and long build times on a 8C/16T laptop with 8GB
* Unexplained recompilation - repeating `make` after a successful build should do nothing. But I found it rebuild a small number of things for reasons that are not clear. Culprits: jemalloc, relinking a few things.
* Faster edit/compile/debug flows for extension developers

The closest thing I could find is this [community docker](https://github.com/getkoala/libduckdb-docker). It can build a ruby extension, but not a C++ extension.

Not a bug. But more of a feature request or a discussion topic.