A global auto parts supplier has announced a $51 million project adding 250 jobs at a rural Kentucky plant. The expansion at the Williamsburg plant is tied to auto industry plans to ramp up electric vehicle production. Company officials said Thursday that stepped up output at the Firestone Industrial Products plant will largely be geared toward producing air suspension systems for electric vehicles. The company plans to break ground soon, with completion expected by late 2022. President Joe Biden’s clean-energy agenda includes a sharp increase in the number of electric vehicles as part of his plan to address climate change.