fix: use dynamic for setInsetsForWebContentToIgnore parameter

`AndroidWebViewInsets` only exists in webview_flutter_android 4.12.0+,
but the mock is also compiled against older resolved versions (3.10.0
for backward compatibility tests, 4.10.x via demo_app's test workspace).
Use `dynamic`, matching the pattern of other version-portable overrides
in this file (`isWebViewFeatureSupported`, `setMixedContentMode`).

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

Author: daohoangson

packages/fwfh_webview/test/mock_webview_platform.dart

@@ -203,9 +203,7 @@ class __FakeAndroidWebViewController extends FakeWebViewController
       throw UnimplementedError();
 
   @override
-  Future<void> setInsetsForWebContentToIgnore(
-    List<AndroidWebViewInsets> insets,
-  ) =>
+  Future<void> setInsetsForWebContentToIgnore(dynamic insets) =>
       throw UnimplementedError();
 
   @override