Treat .magnet file extension as case insensitive

Closes #11200.

src/base/filesystemwatcher.cpp

@@ -160,7 +160,7 @@ void FileSystemWatcher::processTorrentsInDir(const QDir &dir)
     const QStringList files = dir.entryList({"*.torrent", "*.magnet"}, QDir::Files);
     for (const QString &file : files) {
         const QString fileAbsPath = dir.absoluteFilePath(file);
-        if (file.endsWith(".magnet"))
+        if (file.endsWith(".magnet", Qt::CaseInsensitive))
             torrents << fileAbsPath;
         else if (BitTorrent::TorrentInfo::loadFromFile(fileAbsPath).isValid())
             torrents << fileAbsPath;

src/base/scanfoldersmodel.cpp

@@ -360,7 +360,7 @@ void ScanFoldersModel::addTorrentsToSession(const QStringList &pathList)
         else if (!downloadInDefaultFolder(file))
             params.savePath = downloadPathTorrentFolder(file);
 
-        if (file.endsWith(".magnet")) {
+        if (file.endsWith(".magnet", Qt::CaseInsensitive)) {
             QFile f(file);
             if (f.open(QIODevice::ReadOnly | QIODevice::Text)) {
                 QTextStream str(&f);