By Veronika Bondarenko Wendy’s updates a favorite menu item that has been around for over 50 years. Wendy’s (WEN) – Get Wendy’s Company Report square-shaped burgers have been familiar to the fast-food chain’s diners for well over 50 years. Along with Wendy’s iconic burgers, the Frosty is what even those who don’t eat fast food frequently know about and commonly associate with the hamburger chain. The cold dessert that falls somewhere in between a shake and ice cream has been around since 1969 and has retain a loyal following. When the first Wendy’s opened in Columbus, it was one of only five i…