Situation encountered just now after buildah #3949 but
before podman #14084: go.mod changed in such a way that
other modules were updated, not just buildah, and those
changes weren't git-added by 'make vendor'. This resulted
in the dirty-tree CI test failing.
Solution: check for untracked vendor files after 'make vendor',
and git-add them. Show a friendly message that we're doing so:
+---> Adding untracked files under containers/image, containers/storage, klauspost/compress, x/sys
In order to do this safely, we run an untracked-files check
under vendor as one of the first sanity checks. If there are
any when we start the script, fail early.
Signed-off-by: Ed Santiago <santiago@redhat.com>