Clean Params

The new test_blackjack.py file looks like this;

import pytest

from blackjack import card_score

@pytest.mark.parametrize("cards,score", [('JK', 20), ('KKK', 0), ('AA', 12), ('AK', 21)])
def test_simple_usecase(cards, score):
    assert card_score(cards) == score

We hope you agree it is better this way.