Pillagers can spawn in other structures such as cage and tent.

Maybe pillagers spawn in tent are new features, but they shouldn't spawn in the cage.

Steps to Reproduce:

1. Open a new world and find a pillager outpost
2. Use glass pane to find some places pillager can spawn
3. Use some blocks to mark these places.

Observed Results:

Pillager will spawn in the watchtower, cage and tent when you finished to find some places pillager can spawn.

Expected Results:

1. Piallagers don't spawn in the cage.