update Accept-Encoding header to include Brotli compression

src/index.ts

@@ -78,7 +78,7 @@ export default async (
     headers: {
       ...options.headers,
       ...(body ? { "Content-Length": Buffer.byteLength(body) } : {}),
-      "Accept-Encoding": "gzip, deflate"
+      "Accept-Encoding": "br, gzip, deflate"
     }
   };