Add method to get ungenerated chunk from long key (#9254)

Also added a missing deprecation for a location block key method

patches/api/0140-isChunkGenerated-API.patch

@@ -34,14 +34,14 @@ index 16a604b6315daff228c827fe02b1234cca3e884d..20978b269a7757a561d6b872cc77898b
      /**
       * Sets the position of this Location and returns itself
 diff --git a/src/main/java/org/bukkit/World.java b/src/main/java/org/bukkit/World.java
-index 18376c635c689b7aaf1a567bee3d1faaaa28a9f0..4c3150a959593c461f6cf92e9fd8a5f22ff94e8a 100644
+index e83de41cbaf0e5a68ce0d5ad2b5ec10877ec4055..c63a660f2deade66fffad9036ce7c7c693bf0207 100644
 --- a/src/main/java/org/bukkit/World.java
 +++ b/src/main/java/org/bukkit/World.java
-@@ -227,6 +227,17 @@ public interface World extends RegionAccessor, WorldInfo, PluginMessageRecipient
-     public default Chunk getChunkAt(long chunkKey) {
-         return getChunkAt((int) chunkKey, (int) (chunkKey >> 32));
+@@ -245,6 +245,19 @@ public interface World extends RegionAccessor, WorldInfo, PluginMessageRecipient
      }
-+
+     // Paper end - chunk long key API
+ 
++    // Paper start - isChunkGenerated API
 +    /**
 +     * Checks if a {@link Chunk} has been generated at the specified chunk key,
 +     * which is the X and Z packed into a long.
@@ -49,9 +49,11 @@ index 18376c635c689b7aaf1a567bee3d1faaaa28a9f0..4c3150a959593c461f6cf92e9fd8a5f2
 +     * @param chunkKey The Chunk Key to look up the chunk by
 +     * @return true if the chunk has been generated, otherwise false
 +     */
-+    public default boolean isChunkGenerated(long chunkKey) {
++    default boolean isChunkGenerated(long chunkKey) {
 +        return isChunkGenerated((int) chunkKey, (int) (chunkKey >> 32));
 +    }
-     // Paper end
- 
++    // Paper end - isChunkGenerated API
++
      /**
+      * Checks if the specified {@link Chunk} is loaded
+      *