Updated Upstream (Bukkit/CraftBukkit/Spigot)

Upstream has released updates that appears to apply and compile correctly.
This update has not been tested by PaperMC and as with ANY update, please do your own testing

Please note that this build includes changes to meet upstreams
requirements for nullability annotations. While we aim for a level of
accuracy, these might not be 100% correct, if there are any issues,
please speak to us on discord, or open an issue on the tracker to
discuss.

Bukkit Changes:
9a6a1de3 Remove nullability annotations from enum constructors
3f0591ea SPIGOT-2540: Add nullability annotations to entire Bukkit API

CraftBukkit Changes:
8d8475fc SPIGOT-4666: Force parameter in HumanEntity#sleep
8b1588e2 Fix ExplosionPrimeEvent#setFire not working with EnderCrystals
39a287b7 Don't ignore newlines in PlayerListHeader/Footer

Spigot Changes:
cf694d87 Add nullability annotations

Spigot-API-Patches/Fix-ServerListPingEvent-flagging-as-Async.patch

@@ -30,13 +30,13 @@ index eb00d6af..70416c81 100644
 +    // Paper end
  }
 diff --git a/src/main/java/org/bukkit/event/server/ServerListPingEvent.java b/src/main/java/org/bukkit/event/server/ServerListPingEvent.java
-index 343f238f..3c38d857 100644
+index d873763d..b68d7b2f 100644
 --- a/src/main/java/org/bukkit/event/server/ServerListPingEvent.java
 +++ b/src/main/java/org/bukkit/event/server/ServerListPingEvent.java
 @@ -0,0 +0,0 @@ public class ServerListPingEvent extends ServerEvent implements Iterable<Player>
      private int maxPlayers;
  
-     public ServerListPingEvent(final InetAddress address, final String motd, final int numPlayers, final int maxPlayers) {
+     public ServerListPingEvent(@NotNull final InetAddress address, @NotNull final String motd, final int numPlayers, final int maxPlayers) {
 +        super(); // Paper - Is this event being fired async?
          Validate.isTrue(numPlayers >= 0, "Cannot have negative number of players online", numPlayers);
          this.address = address;
@@ -44,7 +44,7 @@ index 343f238f..3c38d857 100644
 @@ -0,0 +0,0 @@ public class ServerListPingEvent extends ServerEvent implements Iterable<Player>
       * @param maxPlayers the max number of players
       */
-     protected ServerListPingEvent(final InetAddress address, final String motd, final int maxPlayers) {
+     protected ServerListPingEvent(@NotNull final InetAddress address, @NotNull final String motd, final int maxPlayers) {
 +        super(); // Paper - Is this event being fired async?
          this.numPlayers = MAGIC_PLAYER_COUNT;
          this.address = address;