Merge pull request #64 from segmentio/authenticator-api-version

fix: Use API version client.authentication.k8s.io/v1beta1

Author: bhavanki

pkg/cluster/kube/kubeconfig.go

@@ -33,7 +33,7 @@ users:
 - name: {{ .Name }}
   user:
     exec:
-      apiVersion: client.authentication.k8s.io/v1alpha1
+      apiVersion: client.authentication.k8s.io/v1beta1
       args:
       - token
       - --region