Don't tick dead players

Causes sync chunk loads and who knows what all else.
This is safe because Spectators are skipped in unloaded chunks too in vanilla.

Spigot-Server-Patches/0458-Don-t-tick-dead-players.patch

@@ -0,0 +1,24 @@
+From 5b6fe0786932553967b817376dc54594178a5977 Mon Sep 17 00:00:00 2001
+From: Aikar <aikar@aikar.co>
+Date: Thu, 2 Apr 2020 17:16:48 -0400
+Subject: [PATCH] Don't tick dead players
+
+Causes sync chunk loads and who knows what all else.
+This is safe because Spectators are skipped in unloaded chunks too in vanilla.
+
+diff --git a/src/main/java/net/minecraft/server/EntityPlayer.java b/src/main/java/net/minecraft/server/EntityPlayer.java
+index e353d93365..f44825090f 100644
+--- a/src/main/java/net/minecraft/server/EntityPlayer.java
++++ b/src/main/java/net/minecraft/server/EntityPlayer.java
+@@ -433,7 +433,7 @@ public class EntityPlayer extends EntityHuman implements ICrafting {
+ 
+     public void playerTick() {
+         try {
+-            if (!this.isSpectator() || this.world.isLoaded(new BlockPosition(this))) {
++            if (valid && (!this.isSpectator() || this.world.isLoaded(new BlockPosition(this)))) { // Paper - don't tick dead players that are not in the world currently (pending respawn)
+                 super.tick();
+             }
+ 
+-- 
+2.25.1
+