HOLYOKE — With gun violence still affecting the community, the city will observe the 12th National Gun Violence Awareness Day on June 3 with a speaking program outside City Hall.City Councilors Israel Rivera and Anne Thalheimer, Holyoke resident Lyn Horan, state Rep. Patricia Duffy, and others affected by gun violence will speak. Mayor Joshua A. Garcia will close the program by reading a proclamation. Local advocacy and violence prevention group…