message: Remove `=>` function
diff: @@ -104,7 +104,7 @@ Authing.prototype = {
  uri: configs.services.user.host,
  fetch: nodeFetch
  });
  - var authMiddleware = new ApolloLink((operation, forward) => {
  + var authMiddleware = new ApolloLink(function (operation, forward) {
  operation.setContext({
  headers: {
  authorization: 'Bearer ' + token
  @@ -187,7 +187,7 @@ Authing.prototype = {
  fetch: nodeFetch
  });
  - var authMiddleware = new ApolloLink((operation, forward) => {
  + var authMiddleware = new ApolloLink(function (operation, forward) {
  operation.setContext({
  headers: {
  authorization: 'Bearer ' + data.data.getAccessTokenByAppSecret,
  @@ -248,7 +248,7 @@ Authing.prototype = {
  uri: configs.services.oauth.host,
  fetch: nodeFetch
  });
  - var authMiddleware = new ApolloLink((operation, forward) => {
  + var authMiddleware = new ApolloLink(function (operation, forward) {
  operation.setContext({
  headers: {
  authorization: 'Bearer ' + self.ownerAuth.token,
  