Endermen mostly don't avoid wither skulls that don't have an Owner

The Bug

Most of the time, endermen fail to teleport away from wither skull projectiles without an Owner, which should be the intended behavior as per MC-178441.

Reproduce

• Summon an Enderman
• Run the following command

  /execute at @e[type=minecraft:enderman] run summon minecraft:wither_skull ~-3 ~2 ~ {NoGravity:1b,Motion:[0.5,0.0,0.0]}
  

Observed Result

The enderman failed to teleport away from the wither skull

Expected Result

Endermen should teleport away from wither skulls as they do with certain projectiles.