Sleep a bit before executing `lava-test-case` to give time for bash to dump shell xtrace messages into
the console, which may cause interleaving with `LAVA_SIGNAL_STARTTC` in some
devices like a618.
The same approach worked for `LAVA_SIGNAL_STARTRUN` since
3b8d10d270 (deafdd86b8d9d0108bc692f479c3b31c4c7d5635_161_164)
was merged.
Closes: #6867
Signed-off-by: Guilherme Gallo <guilherme.gallo@collabora.com>
Reviewed-by: David Heidelberg <david.heidelberg@collabora.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/17533>