Wardens can crawl out and dig in the some illegal blocks that are not normally obtained to survival mode players

Wardens can crawl out and dig in the some illegal blocks that are not normally obtained to survival mode players.

This can cause a lot of trouble for game map creators.
May cause wardens to spawn in places not intended by the map creators.

Affected illegal blocks:

1. Bedrock
2. Barrier
3. Command block
4. Chain command block
5. Repeating command block
6. End portal frame
7. Spawner
8. Structure block