Allow `zone_id` to be runtime value in `spec.get_static_trap`.

[wenjieg]

Passing in zone_id as a parameter to fetch the zone in a kernel does not work (first snippet); only passing the zone as a grid does (second snippet). I'm wondering why this is the case (would naively expect both to work)? Allowing the first case might enable more modular code. @MilanKornjacaQ

@move
def prepare_logical_zero(zone_id: str):
    zone = spec.get_static_trap(zone_id=zone_id)

@move
def prepare_logical_zero(zone: grid.Grid[Any, Any])