[MC-124812] Endermen holding a block can despawn

The bug

Endermen which picked up a block can despawn.

Expected behavior

When endermen pick up a block their PersistenceRequired tag should be set to 1b.

Either the tag should then not be cleared anymore, or better there has to be a tag indicating that PersistenceRequired was set by the player and therefore should not be cleared once the enderman places the block again.

How to reproduce

Create a Superflat world.
Set the time to night.
```
/time set night
```

Summon an enderman holding a stone block.

/summon minecraft:enderman ~ ~ ~ {carriedBlockState:{Name:"minecraft:stone"}}

Teleport away and then back to make sure they could despawn
```
/teleport @s ~ ~ ~1000
/teleport @s ~ ~ ~-1000
```
→ The endermen holding blocks despawned as well