fix potential bugs

backend/bang/expansions/train_robbery/stations.py

@@ -15,6 +15,8 @@ class StationCard:
 
     def discard_and_buy_train(self, player: "Player", card_index: int):
         """Discard the card and buy the train"""
+        if self.attached_train is None:
+            return
         card = player.available_cards.pop(card_index)
         for i, card in enumerate(player.hand):
             if card == self:

frontend/src/components/StationCard.vue

@@ -45,7 +45,7 @@ export default {
     },
     suit() {
       if (this.card && !isNaN(this.card.suit)) {
-        let x = ["♦️", "♣️", "♥️", "♠️", "🤑"];
+        let x = ["♦️", "♣️", "♥️", "♠️", "🤑", "🚂"];
         return x[this.card.suit];
       } else if (this.card.suit) {
         return this.card.suit;