Phoenix: Remove unwanted CSS includes

packages/phoenix/assets/index.html

@@ -5,9 +5,6 @@
     <meta http-equiv="X-UA-Compatible" content="IE=edge">
     <meta name="viewport" content="width=device-width, initial-scale=1.0">
     <title>Document</title>
-    <link rel="stylesheet" href="xterm.css">
-    <link rel="stylesheet" href="normalize.css">
-    <link rel="stylesheet" href="style.css">
     <script src="__SDK_URL__"></script>
     <script src="config.js"></script>
     <script src="bundle.js"></script>