Thirty-four years after she walked into City Hall as an aide to a Dorchester councillor, Maureen Feeney, who served nine terms on the council herself before taking the job of city clerk in 2011, is retiring. The 74-year-old Feeney leaves as her fourth three-year term as clerk ends on Feb. 1. Her career spans five Boston mayors, from Ray Flynn to Michelle Wu. “It just seemed