Axolotls can Spawn Inside Ocean Monuments

Summary: Axolotls spawn in Ocean Monuments.

Steps to Reproduce:
Step 1: Load a world.
Step 2: Locate a Ocean Monument.
Step 3 Repeat.

Observed Result: Axolotls spawn in Ocean Monuments making them vulnerable to Elder Guardians.

Expected Result: Axolotls shouldn't be able to spawn in Ocean Monuments otherwise they immediately get attacked by Elder Guardians.