Explore `--track-untyped` support

[KaanOzkan]

Sorbet now has a built in flag that tracks untyped calls: https://github.com/sorbet/sorbet/pull/6919 sorbet.run

We currently get a similar metric in a snapshot by subtracting the typed calls from all calls. However, this flag gives file specific information which can lead to coverage repors with "untyped calls map".