By Matthew Cooper Alan Shearer would have “hated” playing under Mikel Arteta, admitting he would have been left “embarrassed” by the Arsenal boss’ touchline antics. Arteta has been in charge of the Gunners for over four years now, having returned to the club where he spent five years as a player in 2019, and the Spaniard has a reputation for being one of the more animated managers during games. However, Shearer is not a fan of the way Arteta likes to “manically cajole” his players. “I never worked under an Arteta kind of manager, someone manically cajoling, telling you exactly where to stand o…