Spectator catches on fire when inside of lava cauldron

Steps to Reproduce:

1. Place a cauldron;
2. Fill it with lava;
3. Switch to Spectator Mode;
4. Fly inside of it.

Observed Results:
The spectator catches on fire.

Expected Results:
The spectator doesn't interact with the lava.

Screenshots/Videos attached: Yes

Notes: The fire is only visible to players in spectator mode.