CMakeEditor: Code cosmetics

Change-Id: I44dcd6dbe63e45e870efa9438c7c6f26bf2b06b6
Reviewed-by: David Schulz <david.schulz@qt.io>

src/plugins/cmakeprojectmanager/cmakeeditor.cpp

@@ -109,7 +109,7 @@ QString CMakeEditor::contextHelpId() const
 class CMakeEditorWidget : public TextEditorWidget
 {
 public:
-    CMakeEditorWidget() {}
+    ~CMakeEditorWidget() final = default;
 
 private:
     bool save(const QString &fileName = QString());