Drop unneeded desync patch

spigot no longer even fires the event for this case, so, this may
actually be a regression, not too sure here, but, as-is this patch
is dead

patches/server/0623-fix-cancelling-block-falling-causing-client-desync.patch

@@ -1,19 +0,0 @@
-From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
-From: Trigary <trigary0@gmail.com>
-Date: Sat, 27 Mar 2021 11:13:30 +0100
-Subject: [PATCH] fix cancelling block falling causing client desync
-
-
-diff --git a/src/main/java/net/minecraft/world/entity/item/FallingBlockEntity.java b/src/main/java/net/minecraft/world/entity/item/FallingBlockEntity.java
-index 483127e9418489ad7ba1fbcb14a045d91c1c3c30..880521f25a6c8483c79043f237866cb7a49c3a54 100644
---- a/src/main/java/net/minecraft/world/entity/item/FallingBlockEntity.java
-+++ b/src/main/java/net/minecraft/world/entity/item/FallingBlockEntity.java
-@@ -192,7 +192,7 @@ public class FallingBlockEntity extends Entity {
- 
-                                 // CraftBukkit start
-                                 if (CraftEventFactory.callEntityChangeBlockEvent(this, blockposition, this.blockState).isCancelled()) {
--                                    this.discard(); // SPIGOT-6586 called before the event in previous versions
-+                                    this.discard(); // SPIGOT-6586 called before the event in previous versions //TODO test if desync happens on cancel
-                                     return;
-                                 }
-                                 // CraftBukkit end