Currently, only kubernetes-server-linux-<arch>.tar.gz will be downloaded
and staged for tests. It is not possible to test a cluster where the
platform/arch of the nodes differs from that of the master
control-plane. This changes allows downloading and staging node
binaries, in addition to the existing server binaries.
This should avoid spamming build-log.txt with messages like:
perl: warning: Setting locale failed.
perl: warning: Please check that your locale settings:
LANGUAGE = (unset),
LC_ALL = (unset),
LANG = "en_US.UTF-8"
are supported and installed on your system.
perl: warning: Falling back to the standard locale ("C").
OSX has shasum but not sha1sum, which is part of GNU coreutils.