switch to policy API v1 for PDBs (#2008)

* switch to policy API v1 for PDBs
* update e2e test dependencies
* use kind 0.14.0
* bump K8s client in e2e docker image
* bump e2e tests-runner

pkg/cluster/cluster.go

@@ -29,7 +29,7 @@ import (
 	"github.com/zalando/postgres-operator/pkg/util/volumes"
 	appsv1 "k8s.io/api/apps/v1"
 	v1 "k8s.io/api/core/v1"
-	policybeta1 "k8s.io/api/policy/v1beta1"
+	policyv1 "k8s.io/api/policy/v1"
 	rbacv1 "k8s.io/api/rbac/v1"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	"k8s.io/apimachinery/pkg/types"
@@ -61,7 +61,7 @@ type kubeResources struct {
 	Endpoints           map[PostgresRole]*v1.Endpoints
 	Secrets             map[types.UID]*v1.Secret
 	Statefulset         *appsv1.StatefulSet
-	PodDisruptionBudget *policybeta1.PodDisruptionBudget
+	PodDisruptionBudget *policyv1.PodDisruptionBudget
 	//Pods are treated separately
 	//PVCs are treated separately
 }