add vue2 demo

packages/artplayer-template/vue.js/index.html

@@ -1,13 +0,0 @@
-<!DOCTYPE html>
-<html lang="en">
-  <head>
-    <meta charset="UTF-8" />
-    <link rel="icon" href="/favicon.ico" />
-    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
-    <title>Vite App</title>
-  </head>
-  <body>
-    <div id="app"></div>
-    <script type="module" src="/src/main.js"></script>
-  </body>
-</html>