Anyone with an email address has probably been contacted by a supposed Nigerian prince at some point. The spam messages offering riches from air in exchange for your bank details were once so widespread that they became a running joke. Fortunately, most people probably now know that these generous offers don't come from genuine royalty. But are you as quick when it comes to identifying a fake physical product? A real Nigerian prince is putting people to the test in a campaign for skincare brand Vaseline that's gone viral online. Chris Okagbue is a Nigerian actor and model, but he's also a member of the Onitsha royal family of Anambra State. As a brand ambassador for Vaseline Nigeria, he's been making a series of posts on social media comparing spam emails supposedly sent in his name with fake Vaseline products, which are apparently becoming a problem in Nigeria.…