Improves the error logging in the LAVA job submitter by capturing and logging the exception message rather than just the exception type when a job fails to run. Additionally, introduces a clearer script interruption message to aid in debugging and immediate understanding of job submission failures. Signed-off-by: Guilherme Gallo <guilherme.gallo@collabora.com> Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/28778>