ci/lava: update unit tests

Update unit tests to handle exit code in HWCI result output.

Co-developed-by: Guilherme Gallo <guilherme.gallo@collabora.com>
Signed-off-by: Vignesh Raman <vignesh.raman@collabora.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/31189>
2 files changed