Drop support for "BC Link" format

Fixup 19d6de795c.

src/gui/downloadfromurldialog.cpp

@@ -47,7 +47,6 @@ namespace
             || str.startsWith("https://", Qt::CaseInsensitive)
             || str.startsWith("ftp://", Qt::CaseInsensitive)
             || str.startsWith("magnet:", Qt::CaseInsensitive)
-            || str.startsWith("bc://bt/", Qt::CaseInsensitive)
             || ((str.size() == 40) && !str.contains(QRegularExpression("[^0-9A-Fa-f]")))
             || ((str.size() == 32) && !str.contains(QRegularExpression("[^2-7A-Za-z]"))));
     }

src/gui/search/searchjobwidget.cpp

@@ -261,7 +261,7 @@ void SearchJobWidget::downloadTorrent(const QModelIndex &rowIndex)
     const QString siteUrl = m_proxyModel->data(
                 m_proxyModel->index(rowIndex.row(), SearchSortModel::ENGINE_URL)).toString();
 
-    if (torrentUrl.startsWith("bc://bt/", Qt::CaseInsensitive) || torrentUrl.startsWith("magnet:", Qt::CaseInsensitive)) {
+    if (torrentUrl.startsWith("magnet:", Qt::CaseInsensitive)) {
         addTorrentToSession(torrentUrl);
     }
     else {