修复配置全局变量bug

packages/artplayer/package.json

@@ -1,6 +1,7 @@
 {
   "name": "artplayer",
   "version": "3.1.7",
+  "expose": "Artplayer",
   "description": "ArtPlayer is a modern HTML5 video player",
   "main": "dist/artplayer.js",
   "style": "dist/artplayer.css",

packages/artplayer/src/index.js

@@ -162,5 +162,4 @@ Object.defineProperty(Artplayer, 'instances', {
     value: [],
 });
 
-window.Artplayer = Artplayer;
 export default Artplayer;