SPIGOT-7244: Unable to open Shulker Inventory when more than 8 blocks away

By: md_5 <git@md-5.net>

paper-server/nms-patches/net/minecraft/world/inventory/ContainerShulkerBox.patch

@@ -38,3 +38,11 @@
          iinventory.startOpen(playerinventory.player);
          boolean flag = true;
          boolean flag1 = true;
+@@ -46,6 +66,7 @@
+ 
+     @Override
+     public boolean stillValid(EntityHuman entityhuman) {
++        if (!this.checkReachable) return true; // CraftBukkit
+         return this.container.stillValid(entityhuman);
+     }
+