Players can be idle kicked whilst viewing the end credits

The bug

When viewing the end credits on a server with an idle timeout lower than the duration of the credits, a player can be kicked because they were idle for too long.

How to reproduce

1. Start up a server with an idle timeout shorter than the duration of the end credits. I used one minute for testing.

2. Jump into the end portal as a player that has never seen the end credits before.

3. Wait until you get idle kicked.

Suggested fix

While the player is watching the credits, the variable player.wonGame is set to true. Checking if this value is false before idle kicking the player should be enough to fix this issue.