ci(e2e): disable flaking tests (#9350)

Following our earlier decision, I'm disabling flaking tests. When
amount of disabled tests because of flakes exceed 10, we should
stop other work and focus on fixing flakes.

Signed-off-by: Bart Smykla <bartek@smykla.com>

test/e2e_env/kubernetes/gateway/delegated/meshproxypatch.go

@@ -16,7 +16,8 @@ func MeshProxyPatch(config *Config) func() {
 	GinkgoHelper()
 
 	return func() {
-		It("should add a header using Lua filter", func() {
+		// Disabled because of flakes: https://github.com/kumahq/kuma/issues/9348
+		XIt("should add a header using Lua filter", func() {
 			// given
 			meshProxyPatch := fmt.Sprintf(`
 apiVersion: kuma.io/v1alpha1 

test/e2e_env/universal/reachableservices/reachableservices.go

@@ -42,7 +42,8 @@ func ReachableServices() {
 		}, "30s", "500ms", MustPassRepeatedly(10)).Should(Succeed())
 	})
 
-	It("should not be able to non reachable services", func() {
+	// Disabled because of flakiness: https://github.com/kumahq/kuma/issues/9349
+	XIt("should not be able to non reachable services", func() {
 		Consistently(func(g Gomega) {
 			// when
 			response, err := client.CollectFailure(