Remove useless virtual, better use override only

Signed-off-by: Kevin Ottens <kevin.ottens@nextcloud.com>

test/testoauth.cpp

@@ -230,7 +230,7 @@ private slots:
     {
         // Test that we can send random garbage to the litening socket and it does not prevent the connection
         struct Test : OAuthTestCase {
-            virtual QNetworkReply *createBrowserReply(const QNetworkRequest &request) override {
+            QNetworkReply *createBrowserReply(const QNetworkRequest &request) override {
                 QTimer::singleShot(0, this, [this, request] {
                     auto port = request.url().port();
                     state = CustomState;