Incus image builder for images to be used for the YunoHost dev env, app CI, core CI

Prepare workspace

Before anything, run ./patch_gitlab_runner to generate a small-ish gitlab runner debian package.

Also, the tool needs PyYaml so either install it in your distribution, or you can run pdm install to generate a relevant venv.

How to use

Run ./image_builder.py <version> <distribution> <variants>.

• The version is the Debian version, bullseye or bookworm (or trixie etc).
• The distribution is stable, unstable or testing.
• The variants can be all, appci-only or build-and-lint.

all will build those images:

• before-install - a Debian image with every YunoHost dependency installed, but not YunoHost itself (meant for core CI)
• dev - ditto, but with YunoHost installed, but no postinstall yet (meant for ynh-dev)
• appci- ditto, but with postinstall done (meant for app CI)
• core-tests - ditto, but with a bunch of extra dependencies + pytest modules (meant for core CI)

appci-only will only rebuild appci on top of the existing dev image.

build-and-lint builds a "minimal" Debian image used by the core CI to build .debs, run black/flake/mypy linters etc. (meant for core CI)