By Martin Baccardax Costco’s first quarter earnings missed Street forecasts following a pullback in sales over the final weeks of autumn. Costco Wholesale (COST) – Get Free Report posted weaker-than-expected first quarter earnings Thursday as membership revenues missed Street forecasts amid a pullback in sales over the final weeks of autumn. Costco said diluted earnings for the three months ending on xxx, the company’s fiscal first quarter, came in a $3.09 per share, up 3% from the same period last year but 2 cents shy of the Street consensus forecast Group revenues, Costco said, rose 8.1% to …