Document Next.js config for the mapbox-gl fork. (#1576)

Author: erictheise

docs/get-started/get-started.md

@@ -108,3 +108,19 @@ module.exports = {
   ]
 };
 ```
+
+In Next.js:
+
+```js
+// next.config.js
+const nextConfig = {
+  // ...
+  webpack: (config) => {
+    config.resolve.alias = {
+      ...config.resolve.alias,
+      'mapbox-gl': 'maplibre-gl',
+    };
+  // ...
+  }
+};
+```