Simplify shortcuts code in hamburger menu

src/controller.h

@@ -33,9 +33,6 @@ class Controller : public QObject
     Q_PROPERTY(bool busy READ busy WRITE setBusy NOTIFY busyChanged)
     Q_PROPERTY(KAboutData aboutData READ aboutData WRITE setAboutData NOTIFY aboutDataChanged)
 
-    /// Get the list of shortcuts activating the preferences page
-    Q_PROPERTY(QList<QKeySequence> preferencesShortcuts READ preferencesShortcuts CONSTANT)
-
 public:
     static Controller &instance();
 
@@ -54,8 +51,6 @@ public:
 
     [[nodiscard]] int accountCount() const;
 
-    [[nodiscard]] QList<QKeySequence> preferencesShortcuts() const;
-
     [[nodiscard]] static bool quitOnLastWindowClosed();
     void setQuitOnLastWindowClosed(bool value);