Fix spawn location inconsistency

CraftWorld.setSpawnLocation(Location) requires the world in location.
https://github.com/PaperMC/Paper/blob/e8c6ba5068287049c890688534963041208c4213/paper-server/src/main/java/org/bukkit/craftbukkit/CraftWorld.java#L338

See #3321

Author: riku6460

src/main/java/org/mvplugins/multiverse/core/world/WorldConfigNodes.java

@@ -241,8 +241,8 @@ public Object serialize(Material object, Class<Material> type) {
                 if (!(world instanceof LoadedMultiverseWorld loadedWorld)) return;
                 if (newValue == null || newValue instanceof NullSpawnLocation) return;
                 loadedWorld.getBukkitWorld().peek(bukkitWorld -> {
-                    bukkitWorld.setSpawnLocation(newValue);
                     newValue.setWorld(bukkitWorld);
+                    bukkitWorld.setSpawnLocation(newValue);
                 });
             }));