By Bret Kenwell Home Depot had a strong quarter, but the stock is struggling to maintain its post-earnings gains. Here’s the trade. At one point, retail was one of the few bright spots in the market. Top-performers in the group, like Target (TGT) – Get Target Corporation Report and Costco (COST) – Get Costco Wholesale Corporation Report, were trading well, while others, like Home Depot (HD) – Get Home Depot, Inc. Report were trying to find some upside momentum. The bulls thought they might have found it on Tuesday morning: Home Depot was up 5% at its highs after reporting earnings before the o…