Shares of Dollar General (DG -5.11%) rose early in Thursday's trading session, but then dropped fairly sharply. As of 12:52 p.m. ET, the discount retailer's stock was down by about 4.9% as the market digested the company's lackluster guidance for the coming year.The end of a challenging yearIn its fiscal 2023 (which ended on Feb. 2), Dollar General grew net sales by 2% to almost $39 billion. The top line was boosted by modest same-store sales growth of 0.2%, a notable drop-off from its same-store sales grow ...