Fix created/expires key dates in the users dialog window

--- src/usersdialog.cpp

+++ src/usersdialog.cpp

@@ -150,11 +150,11 @@ void UsersDialog::populateList(const QString &filter) {

         QString userText = user.name + "\n" + user.key_id;

         if (user.created.toSecsSinceEpoch() > 0) {

           userText += " " + tr("created") + " " +

-                      user.created.toString(QLocale::system().toString(QDate::currentDate(), QLocale::ShortFormat));

+                      QLocale::system().toString(user.created, QLocale::ShortFormat);

         }

         if (user.expiry.toSecsSinceEpoch() > 0)

           userText += " " + tr("expires") + " " +

-                      user.expiry.toString(QLocale::system().toString(QDate::currentDate(), QLocale::ShortFormat));

+                      QLocale::system().toString(user.expiry, QLocale::ShortFormat);

         auto *item = new QListWidgetItem(userText, ui->listWidget);

         item->setCheckState(user.enabled ? Qt::Checked : Qt::Unchecked);

         item->setData(Qt::UserRole, QVariant::fromValue(&user));