GitHub操作工作流错误:无法创建文件,路径='/GitHub/home/.flutter'

我正在运行GitHub操作工作流,但由于以下错误而失败。

Unhandled exception:
FileSystemException: Cannot create file, path = '/github/home/.flutter' (OS Error: Permission denied, errno = 13)

我往里面看了看 Workflow syntax for GitHub Actions 但找不到解决这个问题的方法。

我的生成文件如下所示:

name: Flutter CI

on: [push]

jobs:
  build:

    runs-on: ubuntu-latest

    container:
      image:  cirrusci/flutter:v1.7.8-hotfix.4

    steps:
    - uses: actions/checkout@v1
    - name: Install dependencies
      run: flutter pub get
      working-directory: my_app
    - name: Run tests
      run: flutter test