Put the summary of the bug you're having here
Spawners don't stop spawning monsters when covered in torches, they also spawn monsters in the ground.
What I expected to happen was...:
Describe what you thought should happen here
The spawner to stop spawning mobs after light source was added
What actually happened was...:
Describe what happened here
It continuously spawned mobs, in walls and ground as well.
Steps to Reproduce:
1. Find Spawner
2. Add Light Source
3. Wait for Spawner