Working on module 5, detecting check is currently not working as intended

LIST OF CHANGES:
-Chessboard now has a copy constructor to use for detecting check and checkmate, so that I don't have to modify the original board and mess up the game
-Location now has an overloaded constructor that can take in two ints to use those as the column and row
-GameManager now attempts to detect check before Player 1 begins their turn
-GameManager now implements the method to detect check for the white king, although it doesn't seem to work in my initial testing
-GameManager now has a method to get either king's location, used for detecting check