Update github.com/stretchr/testify to v1.2.1
Update github.com/stretchr/testify to v1.2.1

cd $GOPATH/src/k8s.io/kubernetes
hack/godep-restore.sh
rm -rf Godeps
rm -rf vendor
hack/godep-save.sh
hack/update-staging-godeps.sh

Kubernetes-commit: e1cd5eeabcd1816f76b1e31cd2e6c531e4fad6ac

kubernetes/apiextensions-apiserver,kubernetes/apiextensions-apiserver