This unifies the behaviour between the LAVA, baremetal, and CI-Tron
farms by ensuring every job has access and runs the same scripts.
The init-* scripts are however still sourced from outside the build
artifact, hopefully not for too long.
Signed-off-by: Martin Roukala (né Peres) <martin.roukala@mupuf.org>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/33026>