GRAND RAPIDS, Mich. — Calling Patrick Lyoya’s shooting death “an execution” by a police officer, the Rev. Al Sharpton on Friday demanded a federal investigation into the fatal traffic stop. Sharpton, who heads the National Action Network, delivered a half-hour eulogy at the funeral for Lyoya, the motorist killed April 4 by an unnamed Grand Rapids police officer. “I’m not going to desecrate the local authorities, but I want to call on the federal Justice Department to investigate this,” Sharpton said at the Renaissance Church of God in Christ in Grand Rapids. “We don’t want local politics to co…