Update main.dart (#282)

Author: alvinkonda

example/main.dart

@@ -6,7 +6,7 @@ main(List<String> arguments) async {
   // https://developers.google.com/books/docs/overview
   var url = "https://www.googleapis.com/books/v1/volumes?q={http}";
 
-  // Await the http get response, then decode the json-formatted responce.
+  // Await the http get response, then decode the json-formatted response.
   var response = await http.get(url);
   if (response.statusCode == 200) {
     var jsonResponse = convert.jsonDecode(response.body);