docs: update setup content (#124)

* docs: update setup content

* style: remove extra line breaks

* docs: add `defineNuxtConfig` wrapper

---------

Co-authored-by: Daniel Roe <daniel@roe.dev>

docs/content/en/setup.md

@@ -28,6 +28,8 @@ Add `@nuxtjs/google-fonts` dependency to your project:
   </code-block>
 </code-group>
 
+### For Nuxt 2
+
 Then, add `@nuxtjs/google-fonts` to the `buildModules` section of `nuxt.config.js`:
 
 ```js[nuxt.config.js]
@@ -43,3 +45,21 @@ Then, add `@nuxtjs/google-fonts` to the `buildModules` section of `nuxt.config.j
 If you are using Nuxt < v2.9 you have to install the module as a dependency (No --dev or --save-dev flags) and use modules section in nuxt.config.js instead of buildModules.
 
 </alert>
+
+### For Nuxt 3
+
+Then, add `@nuxtjs/google-fonts` to the `modules` section of `nuxt.config.ts`:
+
+```js[nuxt.config.ts]
+export default defineNuxtConfig({
+  modules: [
+    '@nuxtjs/google-fonts'
+  ],
+})
+```
+
+<alert type="warning">
+
+Nuxt modules are now build-time-only, and the `buildModules` property used in Nuxt 2 is deprecated in favor of `modules`.
+
+</alert>