Fixed chunk unloading

By: Dinnerbone <dinnerbone@dinnerbone.com>

paper-server/src/main/java/org/bukkit/craftbukkit/CraftWorld.java

@@ -123,6 +123,7 @@ public class CraftWorld implements World {
             provider.a(chunk);
         }
 
+        provider.a.remove(x, z);
         provider.a.remove(x, z);
         provider.e.remove(x, z);
         provider.f.remove(chunk);