SACRAMENTO, Calif. — A fight over the future of California gig drivers has drawn nearly $220 million in political spending, making it the most expensive initiative in the history of the state.The latest campaign finance reports filed Thursday show that the Yes on Proposition 22 campaign has received nearly $200 million, mostly from five tech companies: Uber, Lyft, DoorDash, Postmates and Instacart.Uber has been the biggest contributor to the campaign, which aims to largely exempt app-based gig economy drivers from a state law that requires companies to provide more employment benefits to their...