Social worker Tara Tisdale, who allegedly sold her clients' private information, was one of those fired from the Human Resources Administration. Call them anti-social workers. Nearly 140 employees from the city Human Resources Administration — the city’s welfare agency — have been axed or forced to resign over the last six years for crimes and misconduct, including an agent charged with keeping food stamps for herself and another who allegedly paid a client to tend to his ferret, according to new data obtained by The Post. The accused cheats included Shamalah Millington, 34, who allegedly concealed her husband’s income to...