getBody method Null safety

Implementation

@override
List<Widget> getBody() => <Widget>[
      _getListTile(
        title: appLocalizations.faq,
        url: 'https://support.openfoodfacts.org/help',
      ),
      _getListTile(
        title: appLocalizations.discover,
        url: 'https://world.openfoodfacts.org/discover',
      ),
      _getListTile(
        title: appLocalizations.how_to_contribute,
        url: 'https://world.openfoodfacts.org/contribute',
      ),
      _getListTile(
        title: appLocalizations.about_this_app,
        onTap: () async => _about(),
        icon: getForwardIcon(),
      ),
    ];