[code-infra] Publish docs from upstream (#47018)

Author: Janpot

docs/package.json

@@ -7,7 +7,7 @@
     "build:clean": "rimraf .next && pnpm build",
     "build-sw": "node ./scripts/buildServiceWorker.js",
     "dev": "next dev",
-    "deploy": "git push -f material-ui-docs master:latest",
+    "deploy": "git fetch upstream master && git push -f material-ui-docs FETCH_HEAD:latest",
     "icons": "rimraf --glob public/static/icons/* && node ./scripts/buildIcons.js",
     "start": "serve ./export",
     "create-playground": "cpy --cwd=scripts playground.template.tsx ../../pages/playground --rename=index.tsx",

scripts/README.md

@@ -4,8 +4,9 @@
 
 ### Prerequisites
 
-1. Make sure you have added the `material-ui-docs` remote to deploy the documentation:
+1. Make sure you have added the `material-ui-docs` and `upstream` remotes to deploy the documentation:
    ```bash
+   git remote add upstream https://github.com/mui/material-ui.git
    git remote add material-ui-docs https://github.com/mui/material-ui-docs.git
    ```
 2. Generate a GitHub Token at https://github.com/settings/personal-access-tokens/new and add it to your shell rc script (either `.bashrc` or `.zshrc`) as `GITHUB_TOKEN`.