Explosions can push spectator players

Explosions caused by TNT, creepers, end crystals, etc, can push spectator players, despite they aren't physically close to it.

How to Reproduce
1. Place down a TNT and lit it up.
2. Switch to spectator mode.
3. Go close to the primed TNT before the explosion happens.

Observed Result
You get pushed by the explosion, despite being in spectator mode.

Expected Result
You shouldn't get pushed by the explosion.