By Evan Bleier Months after watching his Tampa Bay buddy Tom Brady announce his retirement from the NFL before magically deciding to return to the league once a coaching change was underway atop the masthead of the Buccaneers, longtime Patriot and short-time Buc Rob Gronkowski has announced his retirement from pro football. “I will now be going back into my retirement home, walking away from football again with my head held high knowing I gave it everything I had, good or bad, every time I stepped out on the field,” Gronkowski wrote in part in the retirement announcement. “The friendships and …