We should specify what the name of the DB that we'll use will be:

@Test 
public void whenInstantiatedThenMongoHasDbNameTicTacToe() { 
  TicTacToeCollection collection = new TicTacToeCollection(); 
  assertEquals(
     "tic-tac-toe",
     collection.getMongoCollection().getDBCollection().getDB().getName()); 
} 

We are instantiating a new TicTacToeCollection class and verifying that the DB name is what we expect.