buildpackages: zypper refresh before first zypper install
buildpackages: zypper refresh before first zypper install

Refresh is needed to avoid errors like "Media source 'https://...' does not
contain the desired medium" when we use live repositories.

Signed-off-by: Nathan Cutler <f9d8c66a4e898e67db786769b5b347b640e1a9a6@suse.com>

SUSE/teuthology,dmick/teuthology,dmick/teuthology,ceph/teuthology,SUSE/teuthology,dmick/teuthology,SUSE/teuthology,ktdreyer/teuthology,ceph/teuthology,ktdreyer/teuthology