ci/bare-metal: Stop fetching the git tree.

Like for LAVA, make the tradeoff of moving the test scripts and data (55k)
into the artifacts in order to make the per-build jobs not have to pull
down the git tree (hundreds of MB when you don't hit a cached container
for your specific user, which I see happen multiple times a day in my CI
runs).

To do this, we have to be a bit more careful in some places about our
working directory potentially being dirty.

Reviewed-by: Christian Gmeiner <christian.gmeiner@gmail.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/5393>

.gitlab-ci/prepare-artifacts.sh

@@ -23,6 +23,7 @@ find install -name \*.so -exec $STRIP {} \;
 # Test runs don't pull down the git tree, so put the dEQP helper
 # script and associated bits there.
 cp VERSION install/
+cp -Rp .gitlab-ci/bare-metal install/
 cp -Rp .gitlab-ci/deqp* install/
 cp -Rp .gitlab-ci/piglit install/
 cp -Rp .gitlab-ci/traces.yml install/