Don't use deprecated interface.

By: Travis Watkins <amaranth@ubuntu.com>

paper-api/src/main/java/org/bukkit/block/Hopper.java

@@ -1,8 +1,10 @@
 package org.bukkit.block;
 
+import org.bukkit.inventory.InventoryHolder;
+
 /**
  * Represents a hopper.
  */
-public interface Hopper extends BlockState, ContainerBlock {
+public interface Hopper extends BlockState, InventoryHolder {
 
 }