Updates to camera tests to support different delta times and some further tidy-up (#3324)

* updates to camera tests to support different delta times and some further tidy-up

Signed-off-by: hultonha <hultonha@amazon.co.uk>

* support variable delta time in mouse move test

Signed-off-by: hultonha <hultonha@amazon.co.uk>

Code/Framework/AzFramework/AzFramework/Viewport/CameraInput.cpp

@@ -802,7 +802,6 @@ namespace AzFramework
             {
                 return VerticalMotionEvent{ aznumeric_cast<int>(inputChannel.GetValue()) };
             }
-
             else if (inputChannelId == InputDeviceMouse::Movement::Z)
             {
                 return ScrollEvent{ inputChannel.GetValue() };

Code/Framework/AzToolsFramework/AzToolsFramework/Viewport/ViewportMessages.h

@@ -275,9 +275,7 @@ namespace AzToolsFramework
             virtual void BeginCursorCapture() = 0;
             //! Restores the cursor and ends locking it in place, allowing it to be moved freely.
             virtual void EndCursorCapture() = 0;
-            //! Gets the most recent recorded cursor position in the viewport in screen space coordinates.
-            virtual AzFramework::ScreenPoint ViewportCursorScreenPosition() = 0;
-            //! Is mouse over viewport.
+            //! Is the mouse over the viewport.
             virtual bool IsMouseOver() const = 0;
 
         protected: