Fix tests

cluster/service_mux_test.go

@@ -101,9 +101,9 @@ func mustNewTLSMux() (net.Listener, *tcp.Mux) {
 		panic("failed to create mock listener")
 	}
 
-	cert := x509.CertFile("")
+	cert := x509.CertExampleDotComFile("")
 	defer os.Remove(cert)
-	key := x509.KeyFile("")
+	key := x509.KeyExampleDotComFile("")
 	defer os.Remove(key)
 
 	mux, err := tcp.NewTLSMux(ln, nil, cert, key, "", true, false)

cluster/service_test.go

@@ -520,9 +520,9 @@ func mustNewMockManager() *MockManager {
 func mustCreateTLSConfig() *tls.Config {
 	var err error
 
-	certFile := x509.CertFile("")
+	certFile := x509.CertExampleDotComFile("")
 	defer os.Remove(certFile)
-	keyFile := x509.KeyFile("")
+	keyFile := x509.KeyExampleDotComFile("")
 	defer os.Remove(keyFile)
 
 	config := &tls.Config{