Add @NotNull to Key in org.bukkit.sound (#5241)

Fix compiling

Spigot-API-Patches/0005-Adventure.patch

@@ -576,7 +576,7 @@ index a6b9e4f158583e5932bf8ca210d531857e9f5360..d9515a79dc7ed60c66960cd6c6bb4c10
              throw new UnsupportedOperationException("Not supported yet.");
          }
 diff --git a/src/main/java/org/bukkit/Sound.java b/src/main/java/org/bukkit/Sound.java
-index 768f35c19c4557236bded5f4a85f48a2b2b2a9e6..541610054ab13cafcd7fe34e02e1143544ac2511 100644
+index 768f35c19c4557236bded5f4a85f48a2b2b2a9e6..d0ce64412276512cde133937a85a3340a70eea6d 100644
 --- a/src/main/java/org/bukkit/Sound.java
 +++ b/src/main/java/org/bukkit/Sound.java
 @@ -10,7 +10,7 @@ import org.jetbrains.annotations.NotNull;
@@ -588,12 +588,13 @@ index 768f35c19c4557236bded5f4a85f48a2b2b2a9e6..541610054ab13cafcd7fe34e02e11435
  
      AMBIENT_BASALT_DELTAS_ADDITIONS("ambient.basalt_deltas.additions"),
      AMBIENT_BASALT_DELTAS_LOOP("ambient.basalt_deltas.loop"),
-@@ -1016,4 +1016,11 @@ public enum Sound implements Keyed {
+@@ -1016,4 +1016,12 @@ public enum Sound implements Keyed {
      public NamespacedKey getKey() {
          return key;
      }
 +
 +    // Paper start
++    @NotNull
 +    @Override
 +    public net.kyori.adventure.key.@org.checkerframework.checker.nullness.qual.NonNull Key key() {
 +        return this.key;