Fix smartplace destroy blocks

Signed-off-by: yoyosource <yoyosource@nidido.de>

BauSystem_Main/src/de/steamwar/bausystem/features/smartplace/behaviour/BlockRotatingBehaviour.java

@@ -55,6 +55,9 @@ public class BlockRotatingBehaviour implements SmartPlaceBehaviour {
         event.setUseInteractedBlock(Event.Result.DENY);
         World world = event.getPlayer().getWorld();
         Block block = world.getBlockAt(event.getClickedBlock().getX() + event.getBlockFace().getModX(), event.getClickedBlock().getY() + event.getBlockFace().getModY(), event.getClickedBlock().getZ() + event.getBlockFace().getModZ());
+        if (!block.getType().isAir()) {
+            return SmartPlaceResult.IGNORED;
+        }
         block.setType(event.getMaterial());
         blockData = event.getItem().getType().createBlockData();
         BlockFace blockFace = event.getBlockFace();