ATLANTA — Georgia lawmakers voted Thursday to tighten the state’s already strict immigration laws in response to the killing of Laken Riley, a 22-year-old nursing student, whose death became ensnared in the broader fight over immigration policy after a man from Venezuela who entered the country illegally was charged with her murder. In the frenzied final hours of the legislative session, the state’s House of Representatives gave final approval to a measure that would require local law enforcemen