[libcalamaresui] Mark virtual QObject destructors override

src/libcalamaresui/ViewManager.h

@@ -123,7 +123,7 @@ signals:
 
 private:
     explicit ViewManager( QObject* parent = nullptr );
-    virtual ~ViewManager();
+    virtual ~ViewManager() override;
 
     void insertViewStep( int before, ViewStep* step );
 

src/libcalamaresui/modulesystem/ModuleManager.h

@@ -42,7 +42,7 @@ class ModuleManager : public QObject
     Q_OBJECT
 public:
     explicit ModuleManager( const QStringList& paths, QObject* parent = nullptr );
-    virtual ~ModuleManager();
+    virtual ~ModuleManager() override;
 
     static ModuleManager* instance();