The full `git describe` output is not stable across checkouts: the
length of its -g<sha> suffix depends on the local object count, so
build-bundle and build-docker could compute different keys for the same
commit on different runner workspaces. The sha already pins the commit,
so the closest tag is enough to tell versions apart.
Signed-off-by: David Barragán Merino <david.barragan@kaleidos.net>
4b13562d02