Add advanced usage section for GitHub API with octokit installation i…

…nstructions

docs/src/content/docs/reference/scripts/github.md

@@ -97,3 +97,21 @@ Gets the file content for a given ref, tag or commit sha.
 const pkg = await github.getFile("package.json", "main")
 console.log(pkg.content.slice(0, 50) + "...")
 ```
+
+## Advanced use
+
+You can use [octokit](https://www.npmjs.com/package/octokit) to access the full GitHub APIs.
+
+```js
+import { Octokit } from "octokit"
+
+const info = await github.info()
+const client = new Octokit(info)
+...
+```
+
+You will probably need to install it in your list of packages:
+
+```sh
+npm install -D octokit
+```