JAY-Z didn’t hold back when it came to his wrist game at Michael Rubin’s star-studded Fourth of July party in the Hamptons earlier this week. According to professional pocket-watcher and watch connoisseur Chad Alexander, Hov supposedly rocked a rare Patek Phillippe watch worth north of $7million. “JAY-Z wore his vintage yellow gold Patek Phillippe reference 2499,” Alexander said in a …