Add CI test to ensure that kernel metadata up-to-date

When the kernel version is updated, we need to run debian/apertis/update-metadata to ensure that all the scripts and other metadata has been updated with this new version number. If this is not done, the build will fail when pushed to the main branch with a relatively cryptic failure. Test and catch this on merge branches so that we don't have issues on the main branch.

Signed-off-by: Martyn Welch martyn.welch@collabora.com