title: Redirect only the root URL to some other file in Firebase
body: <p>I am using firebase hosting for my web application. </p>
  
  <p>I want to show lp.html at the root of my URL and index.html at everywhere else. To achieve this, I have configured my firebase.json like this:</p>
  
  <pre><code>{
    "hosting": {
      "public": "build/es6-bundled",
      "ignore": [
        "firebase.json",
        "**/.*",
        "**/node_modules/**"
      ],
      "rewrites": [
        {
          "source": "/",
          "destination": "/lp.html"
        },
        {
          "source": "**",
          "destination": "/index.html"
        }
      ]
    }
  }
  </code></pre>
  
  <p>But when I user firebase serve and open <a href="http://localhost:5000/" rel="nofollow noreferrer">http://localhost:5000/</a>, I see the contents from index.html. How can I have the root URL point to lp.html?</p>