Maybe it’s the people of Mexico who should be chanting, “Build that wall!” After they see the new Netflix reality series “Made in Mexico,” which premieres on Friday, they may wish they hadn’t allowed such a free flow of manufactured drama, self-promotion and crocodile tears across the border from the United States.Focusing on nine young socialites (Netflix’s word) living intertwined lives in the wealthier precincts of Mexico City, “Made in Mexico” is an aspirational-reality show that sits about halfway between “Real . . .