BEIJING – Baidu Inc. is among China's tech giants looking to get a leg up in the competitive financial-services market. Credit-rating companies aren't so sure it's a good idea. Fitch recently placed Baidu on negative watch, citing "significantly higher" business risks as it moves into making unsecured consumer loans and selling uninsured investments known as wealth-management products, which Fitch said are "part of the shadow banking system in China." Moody's decided last month to place...