#966 hard-coded `buildkitd-config: /etc/buildkit/buildkitd.toml` inside
the `driver: local` branch of the setup-buildx composite action. The only
caller using that driver is shadow-docker-build.yml, which runs inside
the ghcr.io/nvidia/openshell/ci:latest container — so the host-side
buildkitd.toml was invisible to docker/setup-buildx-action and every
matrix job failed at "Set up buildx".
Revert the hard-coded path and expose it as an opt-in input on the
action (empty default, passed through to both the remote and local
branches). Wire shadow-docker-build.yml to bind-mount /etc/buildkit
into the ci container and pass the path explicitly, so the action can
read the file from inside the container. Remote-driver callers are
unaffected (empty input is a no-op).
Signed-off-by: Jonas Toelke <jtoelke@nvidia.com>
jtoelke2