remove unnecessary override

app/lib/features/geckoview/features/preferences/data/models/preference_setting.dart

@@ -18,9 +18,6 @@ class PreferenceSettingGroup with FastEquatable {
 
   PreferenceSettingGroup({required this.description, required this.settings});
 
-  @override
-  bool get cacheHash => true;
-
   @override
   List<Object?> get hashParameters => [description, settings];
 }
@@ -55,9 +52,6 @@ class PreferenceSetting with FastEquatable {
 
   Map<String, dynamic> toJson() => _$PreferenceSettingToJson(this);
 
-  @override
-  bool get cacheHash => true;
-
   @override
   List<Object?> get hashParameters => [
     value,