Upgrade flutter_web_auth_2

Author: nohli

templates/flutter/pubspec.yaml.twig

@@ -13,7 +13,7 @@ dependencies:
     sdk: flutter
   cookie_jar: ^3.0.1
   device_info_plus: ^8.0.0
-  flutter_web_auth_2: ^1.1.2
+  flutter_web_auth_2: ^2.0.2
   http: ^0.13.5
   package_info_plus: ^3.0.1
   path_provider: ^2.0.11