Gerrit: Force remote refreshing on 401 error

Can happen if the password was changed.

Change-Id: If0f0fa047c376c193ceda50e5465d016e16b61a3
Reviewed-by: Tobias Hunger <tobias.hunger@qt.io>

src/plugins/git/gerrit/gerritmodel.h

@@ -127,6 +127,7 @@ public:
 signals:
     void refreshStateChanged(bool isRefreshing); // For disabling the "Refresh" button.
     void stateChanged();
+    void errorText(const QString &text);
 
 private:
     void resultRetrieved(const QByteArray &);