add empty override for setMethodCallHandler

Author: JulianBissekkou

arcgis_map_sdk_web/lib/src/arcgis_map_sdk_web.dart

@@ -47,6 +47,12 @@ class ArcgisMapWeb extends ArcgisMapPlatform {
     _map(mapId).init();
   }
 
+  @override
+  Future<void> setMethodCallHandler({
+    required int mapId,
+    required Future<dynamic> Function(MethodCall) onCall,
+  }) async {}
+
   @override
   Future<void> moveCamera({
     required LatLng point,