Hardcore mode heart healing animations when having regeneration effect are messed up

When you have regeneration status effect in hardcore mode, the healing animation is messed up. It just doesn't animate up properly when regenerating.

Steps to Reproduce

1. Create a new hardcore mode world with coordinates enabled, with seed number 71
2. Go to the nearest igloo at -168, 88
3. Break the carpet and go to the basement
4. Open the chest and eat the golden apple
5. Watch the health/heart bar animation when regenerating
   ---> The regeneration animation isn't animating correctly, as it stutters.