Updated Upstream (CraftBukkit)

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

CraftBukkit Changes:
4ed5af5e SPIGOT-6956: Reduce differences caused by setKeepSpawnInMemory(false)
21fe78aa SPIGOT-6957: Bad default value for WorldCreator#generatorSettings
ce373be6 PR-1022: Fix get HighestBlockAt in chunk snapshot

patches/server/Configurable-Keep-Spawn-Loaded-range-per-world.patch

@@ -30,11 +30,7 @@ index 0000000000000000000000000000000000000000..00000000000000000000000000000000
  
      // CraftBukkit start
      public void prepareLevels(ChunkProgressListener worldloadlistener, ServerLevel worldserver) {
--        if (!worldserver.getWorld().getKeepSpawnInMemory()) {
--            return;
--        }
 +        ServerChunkCache chunkproviderserver = worldserver.getChunkSource(); // Paper
- 
          // WorldServer worldserver = this.overworld();
          this.forceTicks = true;
          // CraftBukkit end
@@ -49,13 +45,14 @@ index 0000000000000000000000000000000000000000..00000000000000000000000000000000
  
          chunkproviderserver.getLightEngine().setTaskPerBatch(500);
          this.nextTickTime = Util.getMillis();
+-        // CraftBukkit start
+-        if (worldserver.getWorld().getKeepSpawnInMemory()) {
 -            chunkproviderserver.addRegionTicket(TicketType.START, new ChunkPos(blockposition), 11, Unit.INSTANCE);
 -
 -            while (chunkproviderserver.getTickingGenerated() != 441) {
--            // CraftBukkit start
 -                // this.nextTickTime = SystemUtils.getMillis() + 10L;
 -                this.executeModerately();
--            // CraftBukkit end
+-            }
 -        }
 +        // Paper start - configurable spawn reason
 +        int radiusBlocks = worldserver.paperConfig.keepLoadedRange;
@@ -67,7 +64,6 @@ index 0000000000000000000000000000000000000000..00000000000000000000000000000000
 +        worldserver.addTicketsForSpawn(radiusBlocks, blockposition);
 +        // Paper end
  
-         // CraftBukkit start
          // this.nextTickTime = SystemUtils.getMillis() + 10L;
          this.executeModerately();
          // Iterator iterator = this.levels.values().iterator();

work/CraftBukkit

@@ -1 +1 @@
-Subproject commit 86292d3e084729f53ce77af17b7b20d91754b7a5
+Subproject commit 4ed5af5e63dea4884c9466901b4bfb0996455f7e