Ender 6 Cooling Duct

These are the remixes I did for my stock Ender 6 hotend:

1) Reduced the height by 0.8mm to prevent scrapping my build plate
2) Widened the output curvature to avoid touching my heater block
3) Added fillets to bottom sharp corners so it would reduce the chances of catching onto printed parts.
4) Redirected more flow to the back output hole
5) Widened the screw holes by 0.2mm