Some mobs can move while aggro'd even if their movement_speed attribute is 0

Some mobs can move while aggro’d even if their movement_speed attribute is 0. As of right now I have only confirmed this with endermen and zombified piglins but there may be more cases.

To reproduce

1. /summon minecraft:enderman ~ ~ ~ {attributes:[{id:"minecraft:movement_speed",base_value:0d}]}

2. Step back several blocks, go into survival mode and look at the enderman
   Observe how the enderman slowly approaches you even though it should not be able to move

Related issues

MC-278753 is related since a refactor to fix that issue would almost certainly fix this as well.