STOCKTON — Bill Trezza has retired as chief executive officer with the Bank of Agriculture and Commerce Community Bank.Perhaps the last of Stockton’s true community bankers, the 72-year-old native of Orange, New Jersey, spent 37 years with the Stockton-based institution, the past 34 as CEO. On Dec. 31, Trezza stepped down as the longest-tenured CEO of any community bank in the state.