GetViewPortRect().Size -> GetViewportRect().Size (#2338)

* GetViewPortRect().Size -> GetViewport().Size

GetViewPortRect() does not seem to excist anymore so I replaced it with GetViewport().Size

* GetViewportRect() actually excists but with proper casing

tutorials/inputs/mouse_and_input_coordinates.rst

@@ -49,7 +49,7 @@ for example:
             GD.Print("Mouse Motion at: ", eventMouseMotion.Position);
 
         // Print the size of the viewport
-        GD.Print("Viewport Resolution is: ", GetViewPortRect().Size);
+        GD.Print("Viewport Resolution is: ", GetViewportRect().Size);
     }
 
 Alternatively it's possible to ask the viewport for the mouse position: