Fix duplicate theme-color meta tag (codesandbox#2274)

Author: vxna

packages/app/src/app/index.html

@@ -19,7 +19,6 @@
 	<meta property="twitter:image:src" content="https://codesandbox.io/static/img/banner.png">
 	<meta property="twitter:image:width" content="1200">
 	<meta property="twitter:image:height" content="630">
-	<meta name="theme-color" content="#40A9F3">
 	<meta name="description" content="CodeSandbox is an online editor tailored for web applications.">
 	<link rel="shortcut icon" href="/favicon.ico">
 	<link rel="manifest" href="/manifest.json">

packages/app/src/embed/index.html

@@ -19,7 +19,6 @@
     <meta property="twitter:image:src" content="https://codesandbox.io/static/img/banner.png">
     <meta property="twitter:image:width" content="1200">
     <meta property="twitter:image:height" content="630">
-    <meta name="theme-color" content="#40A9F3">
     <meta name="description" content="CodeSandbox is an online editor tailored for web applications.">
     <link href="https://fonts.googleapis.com/css?family=Roboto:300,400,500,700|Source Code Pro:500" rel="stylesheet">
     <link rel="manifest" href="/manifest.json">