Promotion moves not implemented in ChessMove::from_san

[Gourab-Ghosh]

Promotion moves not implemented in ChessMove::from_san. In position 8/7P/2p5/p1n2k2/6R1/5P2/p6K/2r5 w - - 0 1 calling the function ChessMove::from_san(board, "h8=Q") panics.

[kesslwovv]

Promotions are supported, just without the equal sign. ChessMove::from_san(board, "h8Q") will work.
My workaround was to remove all "=" before calling from_san.