test: added test for setGame Winner

src/test/java/cz/muni/fi/pa165/icehockeymanager/services/GameServiceImplTest.java

@@ -111,6 +111,15 @@ class GameServiceImplTest {
         verify(gameDao).update(game);
     }
 
+    @Test
+    public void setGameWinner() {
+        Game game = buildGame();
+        Team team = buildTeam("CSKA Moskva");
+        gameService.setGameWinner(game, team);
+        assertThat(game.getWinner().get()).isEqualTo(team);
+        verify(gameDao).update(game);
+    }
+
     private Team buildTeam(String name) {
         return buildTeam(1L, name);
     }