You can no longer swim when crouched under a slab

In versions before 24w44a, you could swim when in crouching mode under a slab.
Now, you are no longer able to swim when in this state. This is most likely caused by the fix of MC-152728.

 h3. Steps to reproduce

1. Go into water with a slab above you so that you are crouched
2. Try to swim by sprinting
   You can not swim