findAround
Finds all coordinates with 1 cell distance from the given piece that contain the specified type of piece.
Return
A list of coordinates where the specified type of piece is found around the given piece.
Parameters
board
The current state of the board.
myPiece
The piece around which to search.
findThis
The type of piece to search for. If null, it will find empty spaces.
Throws
if the position is out of bounds.