fix: Removed deprecated code and unused import causing CI to fail (#59)

Author: pratikbaid3

lib/api/api_requests.dart

@@ -345,7 +345,7 @@ class ApiRequests {
             'href': rssItem.url,
             'rss': labelHash,
           });
-      var xmlResponse = xml.parse(response.body);
+      var xmlResponse = xml.XmlDocument.parse(response.body);
 
       var data =
           xmlResponse.lastChild.text; // extracting value stored in data tag

lib/pages/torrents_list_page.dart

@@ -8,7 +8,6 @@ import 'package:rutorrentflutter/components/torrent_tile.dart';
 import 'package:rutorrentflutter/models/general_features.dart';
 import 'package:rutorrentflutter/models/torrent.dart';
 import '../components/loading_shimmer.dart';
-import '../utilities/constants.dart';
 
 class TorrentsListPage extends StatelessWidget {
   checkForActiveDownloads(Api api, GeneralFeatures general) async {