Shulkers open into other shulkers when unable to teleport. This issue is related to MC-93477

What I expected to happen was...:
The shulker should have been unable to open when another shulker was in the way of its shell opening.

What actually happened was...:
The shulker continued to open, clipping into the shulker blocking the path of its shell.

Steps to Reproduce:

1. Build the structure detailed in the attachments high enough in the air that the shulkers cannot teleport to any other blocks in the area (make sure to place all the buttons).
2. Place the shulkers as shown:
3. Place a piston above the upper shulker facing down:
4. Place a redstone torch at the top of the structure:
5. Observe the shulkers for a few seconds.