intel: properly escape sed pattern for tests

intel: properly escape sed pattern for tests

The sed was incorrectly modifying e.g. "nicholasbishop" to
"nicholasbop". The updated pattern will only match `.sh` at the end of
the string.

Signed-off-by: Nicholas Bishop <nicholasbishop@gmail.com>
Reviewed-by: Emil Velikov <emil.velikov@collabora.com>