Node.js 12 actions are deprecated. Please update the following actions to use Node.js 16: actions/checkout@v2, bilelmoussaoui/flatpak-github-actions/flatpak-builder@v3. For more information see: https://github.blog/changelog/2022-09-22-github-actions-all-actions-will-begin-running-on-node16-instead-of-node12/.