better createGameTest

fh.fd.ci.server/src/test/java/de/fd/fh/server/game/GameServiceTest.java

@@ -14,7 +14,7 @@ class GameServiceTest
     void testCreateGame()
     {
         final GameRepository repository = when(mock(GameRepository.class).save(any()))
-                .thenReturn(new Key<>(Game.class, "testCollection", GameId.random()))
+                .thenReturn(new Key<>(Game.class, "testCollection", GameId.of("98765")))
                 .getMock();
 
         final Game game = new Game();
@@ -22,5 +22,6 @@ class GameServiceTest
         final GameId result = new GameService(repository).createGame(game);
 
         assertNotNull(result);
+        assertEquals("98765", result.getIdentifier());
     }
 }