Remove the scrollbar triggered by dragging a card downwards

[Muthaias]

To replicate:

• Drag card towards the bottom of the screen such that it passes the bottom of the window
• A scrollbar appears (This scrollbar should be disabled)

[Greenheart]

Fixed by https://github.com/Greenheart/swipeforfuture.com/commit/f4c769216438f9d77170b9b4693a197ed9f9170f