tests/lcitool: Delete obsolete centos-stream-8.yml file

tests/lcitool: Delete obsolete centos-stream-8.yml file

We've missed to delete this file when removing support for CentOS 8.
Since the current upstream version of the lcitool removed support
for CentOS 8 now, too, we have to remove the file before updating.

Signed-off-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Message-Id: <20240601070543.37786-2-thuth@redhat.com>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20240603175328.3823123-8-alex.bennee@linaro.org>