Summon a ender dragon in a custom dimension will crash the game.

What I expected to happen was...:
The ender dragon triggered java.lang.IllegalArgumentException:  bound must be positive

What actually happened was...:
There's a player that in survival mode in another dimension of the world, and the system will spawn a ender dragon for he to fight, then it crash the game.

Steps to Reproduce:
1. Make a datapack to generate a dimension for player
2. Teleport into the dimension
3. Run the command /summon minecraft:ender_dragon ~ ~ ~ {DragonPhase:0} in survival mode