test: Disable flaky etcd test

Disable on all pipelines except for K8s 1.11/Linux net-next, since the
test never flaked on that one so far.

Signed-off-by: Paul Chaignon <paul@cilium.io>

test/k8sT/DatapathConfiguration.go

@@ -550,7 +550,8 @@ var _ = Describe("K8sDatapathConfig", func() {
 	})
 
 	Context("Etcd", func() {
-		It("Check connectivity", func() {
+		// Flaky on pipelines other than K8s 1.11/Linux net-next.
+		SkipItIf(helpers.DoesNotRunOnNetNextKernel, "Check connectivity", func() {
 			deploymentManager.Deploy(helpers.CiliumNamespace, StatelessEtcd)
 			deploymentManager.WaitUntilReady()