Firebase hosting: Why firebase hosted my all the source code into there hosting? How can I restrict only to "build" folder?

I have build a react app and I used firebase hosting to deploy my app. It's working fine but firebase has hosted all the source code. I only need to upload build folder. How can I remove other files from the hosting?

firebase.json

{
  "hosting": {
    "public": "build",
    "ignore": [
      "firebase.json",
      "**/.*",
      "**/node_modules/**"
    ],
    "rewrites": [
      {
        "source": "**",
        "destination": "/index.html"
      }
    ]
  }
}

Is there any thing to do?

But somehow I have uploaded build folder only for another app But I cannot remember/find how I did it, I see no different between firebase.json

firebase,json

{
  "hosting": {
    "public": "build",
    "ignore": [
      "firebase.json",
      "**/.*",
      "**/node_modules/**"
    ],
    "rewrites": [
      {
        "source": "**",
        "destination": "/index.html"
      }
    ]
  }
}