In test_board.py test_delete_cards fails

[dstengle]

It seems as if this test is meant for closing cards.

It is taking number of closed cards as "deleted", number of open cards deleting all open cards then looking for current closed cards to be equal to "deleted" + number open cards.

Either the API used to delete open cards by closing them and this test used to work or something is wrong with the test.

Happy to submit a fix for either closing or deleting or both.