Added apple gamekit auth

Untested rn

src/Adapters/Auth/index.js

@@ -18,6 +18,7 @@ const wechat = require("./wechat");
 const weibo = require("./weibo");
 const steam = require("./steam");
 const nintendo = require("./nintendo");
+const apple = require("./apple");
 
 const anonymous = {
   validateAuthData: () => {
@@ -47,7 +48,8 @@ const providers = {
   wechat,
   weibo,
   steam,
-  nintendo
+  nintendo,
+  apple
 }
 function authDataValidator(adapter, appIds, options) {
   return function(authData) {