tests/docker: auto-generate fedora.docker with lcitool

This commit is best examined using the "-b" option to diff.

Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20211215141949.3512719-10-berrange@redhat.com>
Message-Id: <20220105135009.1584676-10-alex.bennee@linaro.org>