fix block rotation using facing=down and facing=up

Author: ZakShearman

src/main/java/net/hollowcube/schem/CoordinateUtil.java

@@ -115,7 +115,8 @@ private static String rotate90(String in) {
             case "north" -> "east";
             case "east" -> "south";
             case "south" -> "west";
-            default -> "north";
+            case "west" -> "north";
+            default -> in;
         };
     }