docs: add github in sources (#1946)

docs/content/4.api/3.configuration.md

@@ -81,7 +81,7 @@ The watcher is a development feature and will not be included in production.
 
 Define different sources for contents.
 
-Contents can be located in multiple places, in multiple directories, or in remote git repositories.
+Contents can be located in multiple places, in multiple directories, or in remote git repositories thanks to [`unstorage`](https://unstorage.unjs.io/).
 
 ```ts [nuxt.config.ts]
 export default defineNuxtConfig({
@@ -99,7 +99,15 @@ export default defineNuxtConfig({
         driver: 'fs',
         // ...driverOptions
         base: resolve(__dirname, 'content-fa') // Path for source directory
-      }
+      },
+      github: {
+        prefix: '/blog', // Prefix for routes used to query contents
+        driver: 'github', // Driver used to fetch contents (view unstorage documentation)
+        repo: "<owner>/<repo>",
+        branch: "main",
+        dir: "content", // Directory where contents are located. It could be a subdirectory of the repository.
+        // Imagine you have a blog inside your content folder. You can set this option to `content/blog` with the prefix option to `/blog` to avoid conflicts with local files.
+      },
     }
   }
 })