Fix #17339. Reset Scaleing frame buffers on scale change (#17598)

* Fix #17339. Poor visuals due to scalling incorrectly

Mistake made during refactor meant that the scaleing framebuffers were
kept enabled even though at integer numbers of scale they are not meant
to be used.

* Update changelog

src/openrct2-ui/drawing/engines/opengl/OpenGLDrawingEngine.cpp

@@ -444,6 +444,8 @@ private:
     {
         // Re-create screen framebuffer
         _screenFramebuffer = std::make_unique<OpenGLFramebuffer>(_window);
+        _smoothScaleFramebuffer.reset();
+        _scaleFramebuffer.reset();
         if (GetContext()->GetUiContext()->GetScaleQuality() != ScaleQuality::NearestNeighbour)
         {
             _scaleFramebuffer = std::make_unique<OpenGLFramebuffer>(_width, _height, false, false);