[1.16.5] Forge TimeTracker is removed in your LevelMixin

[Kasualix]

https://github.com/tasgon/observable/blob/master/common/src/main/java/observable/mixin/LevelMixin.java#L30

https://github.com/MinecraftForge/MinecraftForge/blob/1.16.x/patches/minecraft/net/minecraft/world/World.java.patch#L229

Btw maybe you can change the overwrite to redirect? I haven't looked closely but it feels like it should work, to be less invasive