How to disable graphql playground?

My angular application is configured with graphql which by default enabled with playground, how to disable it? following is my
package.json

  "dependencies": {
    "@nestjs/common": "^7.0.8",
    "@nestjs/core": "^7.0.8",
    "@nestjs/graphql": "^7.3.4",
    "@nestjs/microservices": "^7.0.8",
    "class-transformer": "^0.2.3",
    "class-validator": "^0.12.2",
    "graphql": "^14.0.0",
    "reflect-metadata": "^0.1.12",
    "rxjs": "^6.0.0"
  }

and Dockerfile

FROM node:16
RUN mkdir -p /testappservice/app

COPY dist/apps/testappservice-container testappservice/app
COPY apps/testappservice/build/docker/package.json testappservice

WORKDIR /testappservice
RUN yarn install

ENV PORT 80
ENV NODE_TLS_REJECT_UNAUTHORIZED 0
ENV NODE_ENV=production
CMD ["node", "app/index.js"]