UsingActionToAutomatePublishingPages

name: Github Pages
on:
  workflow_dispatch:
  push:
    branches:
      - master
jobs:
  Deploy-Pages:
    runs-on: ubuntu-latest
    steps:
      - name: Checkout
        uses: actions/checkout@v2

      - name: Install Deps
        run: yarn install

      - name: Build App
        run: yarn build

      - name: Deploy
        uses: peaceiris/actions-gh-pages@v3
        with:
          github_token: ${{ secrets.GITHUB_TOKEN }}
          publish_dir: ./build

1. The prefix - represents an array element, and the content of the element ends with the next -.
2. GITHUBTOKEN in secrets.GITHUBTOKEN is a default token, which does not require additional configuration.