The following action / job will download and save latest pwa-studio source code to your github repo using magento-actions.
Also one can use this repo as template.
name: 'install & push pwa-studio project'
- uses: actions/checkout@v2
- name: 'install fresh pwa studio code and copy to repo'
#no_push: 1 //uncomment this to prevent files from getting pushed to repo
Video tutorial on how to install pwa-studio