Fix unlocked maps getting wrongly locked

bukkit/src/main/java/net/william278/husksync/data/BukkitMapHandler.java

@@ -77,7 +77,7 @@ public class BukkitMapHandler {
         }
 
         final MapMeta mapMeta = (MapMeta) itemStack.getItemMeta();
-        if (mapMeta == null) {
+        if (mapMeta == null || mapMeta.getMapView() == null || !mapMeta.getMapView().isLocked()) {
             return;
         }