message: cli: update public/index.html in app template
diff: name="description"
  content="Backstage is an open platform for building developer portals"
  />
  - <link rel="apple-touch-icon" href="%PUBLIC_URL%/logo192.png" />
  + <link rel="apple-touch-icon" href="<%= publicPath %>/logo192.png" />
  <!--
  manifest.json provides metadata used when your web app is installed on a
  user's mobile device or desktop. See https://developers.google.com/web/fundamentals/web-app-manifest/
  -->
  <link
  rel="manifest"
  - href="%PUBLIC_URL%/manifest.json"
  + href="<%= publicPath %>/manifest.json"
  crossorigin="use-credentials"
  />
  - <!--
  - Notice the use of %PUBLIC_URL% in the tags above.
  - It will be replaced with the URL of the `public` folder during the build.
  - Only files inside the `public` folder can be referenced from the HTML.
  -
  - Unlike "/favicon.ico" or "favicon.ico", "%PUBLIC_URL%/favicon.ico" will
  - work correctly both with client-side routing and a non-root public URL.
  - Learn how to configure a non-root public URL by running `npm run build`.
  - -->
  - <link rel="icon" href="%PUBLIC_URL%/favicon.ico" />
  - <link rel="shortcut icon" href="%PUBLIC_URL%/favicon.ico" />
  + <link rel="icon" href="<%= publicPath %>/favicon.ico" />
  + <link rel="shortcut icon" href="<%= publicPath %>/favicon.ico" />
  <link
  rel="apple-touch-icon"
  sizes="180x180"
  - href="%PUBLIC_URL%/apple-touch-icon.png"
  + href="<%= publicPath %>/apple-touch-icon.png"
  />
  <link
  rel="icon"
  type="image/png"
  sizes="32x32"
  - href="%PUBLIC_URL%/favicon-32x32.png"
  + href="<%= publicPath %>/favicon-32x32.png"
  />
  <link
  rel="icon"
  type="image/png"
  sizes="16x16"
  - href="%PUBLIC_URL%/favicon-16x16.png"
  + href="<%= publicPath %>/favicon-16x16.png"
  />
  <link
  rel="mask-icon"
  - href="%PUBLIC_URL%/safari-pinned-tab.svg"
  + href="<%= publicPath %>/safari-pinned-tab.svg"
  color="#5bbad5"
  />
  <style>
  min-height: 100%;
  }
  </style>
  - <title>Backstage</title>
  + <title><%= app.title %></title>
  </head>
  - <body style="margin: 0">
  + <body style="margin: 0;">
  <noscript>You need to enable JavaScript to run this app.</noscript>
  <div id="root"></div>
  <!--
  