By Paresh Dave OAKLAND, Calif. (Reuters) – Delta Air Lines Inc, Kellogg Co and several big ad agencies on Monday pledged to counteract unwanted biases in the algorithms that power their online advertising. The action, announced as part of an ad industry conference in Cannes, France, is one of the biggest steps taken to ensure stereotypes related to gender, race and other characteristics are not unfairly deciding to whom an ad is shown. Growing use of automated software to buy ads, greater attention on diversity and the looming risk of scrutiny from consumer protection regulators has brought ur…