test/e2e: fix flake for on delete on namespace

Signed-off-by: Jess Frazelle <me@jessfraz.com>

test/e2e/kubectl.go

@@ -987,7 +987,17 @@ var _ = framework.KubeDescribe("Kubectl client", func() {
 		})
 
 		AfterEach(func() {
-			framework.RunKubectlOrDie("delete", "deployment", dName, nsFlag)
+			err := wait.Poll(framework.Poll, 2*time.Minute, func() (bool, error) {
+				out, err := framework.RunKubectl("delete", "deployment", dName, nsFlag)
+				if err != nil {
+					if strings.Contains(err.Error(), "could not find default credentials") {
+						err = nil
+					}
+					return false, fmt.Errorf("kubectl delete failed output: %s, err: %v", out, err)
+				}
+				return true, nil
+			})
+			Expect(err).NotTo(HaveOccurred())
 		})
 
 		It("should create a deployment from an image [Conformance]", func() {