Maven Gig, the car-sharing service for gig economy workers owned by General Motors, is expanding to a few more cities. Starting today, the service is available in Los Angeles. Later this fall, it will launch in Boston, Phoenix, and Washington, DC. And Baltimore and Detroit will follow soon after. The program is aimed at drivers for rideshare apps like Uber and Lyft, and delivery apps like Postmates, GrubHub, and InstaCart. Someone who’s interested in driving