Fix double delete in QgsMeasureTool

The rubber bands are owned by the canvas - so we shouldn't
be deleting them here.

src/app/qgsmeasuretool.cpp

@@ -56,14 +56,6 @@ QgsMeasureTool::QgsMeasureTool( QgsMapCanvas *canvas, bool measureArea )
   connect( canvas, &QgsMapCanvas::destinationCrsChanged, this, &QgsMeasureTool::updateSettings );
 }
 
-QgsMeasureTool::~QgsMeasureTool()
-{
-  delete mDialog;
-  delete mRubberBand;
-  delete mRubberBandPoints;
-}
-
-
 QVector<QgsPointXY> QgsMeasureTool::points()
 {
   return mPoints;

src/app/qgsmeasuretool.h

@@ -35,8 +35,6 @@ class APP_EXPORT QgsMeasureTool : public QgsMapTool
 
     QgsMeasureTool( QgsMapCanvas *canvas, bool measureArea );
 
-    ~QgsMeasureTool() override;
-
     Flags flags() const override { return QgsMapTool::AllowZoomRect; }
 
     //! returns whether measuring distance or area