Fixed other bug

src/main/kotlin/extensions.kt

 import model.Card
 
 fun List<Card>.clone() = mutableListOf<Card>().also {
-    forEach { c ->
-        it.add(it.javaClass.constructors[0].newInstance(c.isFaceUp, c.cardValue) as Card)
+    forEach { card ->
+        it.add(card.javaClass.constructors[0].newInstance(card.isFaceUp, card.cardValue) as Card)
     }
 }
 

src/test/kotlin/model/PSTestFile.kt

@@ -27,6 +27,7 @@ class PSTestFile {
         val deck = GamePile()
         val deck2 = deck.addSingleCardAndReturnNewDeck(HeartCard(true, CardValue.KING))
         assertThat(deck2).isNotNull.isEqualTo(Deck(mutableListOf(HeartCard(true, CardValue.KING))))
+        assertThat(deck2!!.addSingleCardAndReturnNewDeck(HeartCard(true, CardValue.TEN))).isNotNull.isEqualTo(Deck(mutableListOf(HeartCard(true, CardValue.KING),HeartCard(true, CardValue.TEN) )))
         assertThat(deck.addSingleCardAndReturnNewDeck(HeartCard(true, CardValue.TEN))).isNull()
     }