Fix: removed a critical callback during refactor
Fix: removed a critical callback during refactor

arbrandes/xblock-drag-and-drop-v2,edx-solutions/xblock-drag-and-drop-v2,edx-solutions/xblock-drag-and-drop-v2,arbrandes/xblock-drag-and-drop-v2,open-craft/xblock-drag-and-drop-v2,edx-solutions/xblock-drag-and-drop-v2,open-craft/xblock-drag-and-drop-v2,arbrandes/xblock-drag-and-drop-v2,open-craft/xblock-drag-and-drop-v2,arbrandes/xblock-drag-and-drop-v2,edx-solutions/xblock-drag-and-drop-v2,open-craft/xblock-drag-and-drop-v2