fixed spectator mode after playing tetris

src/main/java/eu/mhsl/minenet/minigames/instance/game/stateless/types/tetris/Tetris.java

@@ -112,9 +112,11 @@ class Tetris extends StatelessGame {
 
     private void letPlayerLoose(Player player) {
         TetrisGame tetrisGame = this.tetrisGames.get(player);
+        if(!this.getScore().hasResult(player)) {
             player.setGameMode(GameMode.SPECTATOR);
             player.setInvisible(true);
             this.getScore().insertResult(player, tetrisGame.getScore());
+        }
 
         boolean allGamesLost = this.tetrisGames.values().stream()
             .filter(game -> !game.lost)