Authenticating git and gh-cli using GitHub Apps in GitHub Actions

Using GitHub Apps instead of Personal Access Tokens or SSH keys for authentication in GitHub Actions workflows offers better security through short-lived tokens and easier reuse across repositories. The guide covers creating a GitHub App with appropriate permissions (Contents and Pull Requests), generating a private key, installing the App on repositories, and then using the `actions/create-github-app-token` action to obtain a token. The token can authenticate `actions/checkout`, the `gh` CLI via the `GH_TOKEN` environment variable, and git commits with properly configured bot author information.