Fix the extra slot item in input buses not dropping

Author: Zorbatron

src/main/java/gregtech/common/metatileentities/multi/multiblockpart/appeng/MetaTileEntityMEInputBus.java

@@ -161,6 +161,14 @@ protected void syncME() {
         }
     }
 
+    @Override
+    public void clearMachineInventory(@NotNull List<@NotNull ItemStack> itemBuffer) {
+        ItemStack extraSlotStack = extraSlotInventory.getStackInSlot(0);
+        if (!extraSlotStack.isEmpty()) {
+            itemBuffer.add(extraSlotStack);
+        }
+    }
+
     @Override
     public void onRemoval() {
         flushInventory();