Things like `luma(1, key: "val")` didn't produce an error before because `args.finish()?` wasn't called. This changes `args: Args` to `args: &mut Args` to make it impossible for that to happen.
Things like `luma(1, key: "val")` didn't produce an error before because `args.finish()?` wasn't called. This changes `args: Args` to `args: &mut Args` to make it impossible for that to happen.