Update client callers to use explicit versions

plugin/pkg/admission/namespace/autoprovision/admission.go

@@ -89,7 +89,7 @@ func (p *Provision) Admit(a admission.Attributes, o admission.ObjectInterfaces)
 		Status: corev1.NamespaceStatus{},
 	}
 
-	_, err = p.client.Core().Namespaces().Create(namespace)
+	_, err = p.client.CoreV1().Namespaces().Create(namespace)
 	if err != nil && !errors.IsAlreadyExists(err) {
 		return admission.NewForbidden(a, err)
 	}

plugin/pkg/admission/namespace/exists/admission.go

@@ -75,7 +75,7 @@ func (e *Exists) Validate(a admission.Attributes, o admission.ObjectInterfaces)
 	}
 
 	// in case of latency in our caches, make a call direct to storage to verify that it truly exists or not
-	_, err = e.client.Core().Namespaces().Get(a.GetNamespace(), metav1.GetOptions{})
+	_, err = e.client.CoreV1().Namespaces().Get(a.GetNamespace(), metav1.GetOptions{})
 	if err != nil {
 		if errors.IsNotFound(err) {
 			return err