Remove now unneeded patch due to paperweight 1.1.7

patches/server/0721-Fix-chicken-jockey-persistence.patch

@@ -1,19 +0,0 @@
-From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
-From: KennyTV <jahnke.nassim@gmail.com>
-Date: Sat, 26 Jun 2021 10:43:53 +0200
-Subject: [PATCH] Fix chicken jockey persistence
-
-
-diff --git a/src/main/java/net/minecraft/world/entity/animal/Chicken.java b/src/main/java/net/minecraft/world/entity/animal/Chicken.java
-index 8460bed561c09a647f6e0209f7c5448e5a42b281..9a4b133e4ecbd04753f55d9c4a8bd1ed83943476 100644
---- a/src/main/java/net/minecraft/world/entity/animal/Chicken.java
-+++ b/src/main/java/net/minecraft/world/entity/animal/Chicken.java
-@@ -77,7 +77,7 @@ public class Chicken extends Animal {
-     public void aiStep() {
-         // CraftBukkit start
-         if (this.isChickenJockey()) {
--            this.persistenceRequired = !this.removeWhenFarAway(0);
-+            ((Mob) this).persistenceRequired = !this.removeWhenFarAway(0); // Paper - fix remap by explicitly casting to Mob
-         }
-         // CraftBukkit end
-         super.aiStep();