Refactor magnet link copy function

The function for copying the magnet link has been refactored. The code now uses a more pythonic way to filter valid URLs from trackers and handles missing keys in the current download dictionary gracefully. This change improves readability and robustness of the code.

src/tribler/gui/widgets/downloadsdetailstabwidget.py

@@ -198,12 +198,17 @@ def update_pages(self, new_download=False):
                 item = QTreeWidgetItem(self.window().download_peers_list)
                 DownloadsDetailsTabWidget.update_peer_row(item, peer)
 
-    def on_copy_magnet_clicked(self, checked):
-        trackers = [
-            tk['url'] for tk in self.current_download['trackers'] if 'url' in tk and tk['url'] not in ['[DHT]', '[PeX]']
-        ]
+    def on_copy_magnet_clicked(self, _):
+        """ Copy the magnet link of the current download to the clipboard."""
+        invalid_urls = {'[DHT]', '[PeX]'}
+        trackers = self.current_download.get('trackers', [])
+        urls = (t.get('url') for t in trackers)
+        valid_urls = [u for u in urls if u not in invalid_urls]
+
         magnet_link = compose_magnetlink(
-            self.current_download['infohash'], name=self.current_download.get('name', None), trackers=trackers
+            infohash=self.current_download.get('infohash'),
+            name=self.current_download.get('name'),
+            trackers=valid_urls
         )
         copy_to_clipboard(magnet_link)
         self.window().tray_show_message(tr("Copying magnet link"), magnet_link)