Minneapolis — Target cut its profit and comparable-store sales outlook amid stiffer competition and its own stumbles in areas like grocery sales. The discounter’s second-quarter net income fell nearly 10%, though that was better than what most had expected. Sales at stores open at least a year fell 1.1%, reversing seven straight quarters of gains. Target shares were down more than 6% in mid-morning trading Wednesday. The quarter underscores challenges that Target and other retailers face from Amazon.com and shoppers who remain cautious about spending.