`untyped-import` but for libraries with no known stubs package

[`untyped-import` only seems to report an error if there's a known stubs package](https://pyrefly.org/en/docs/error-kinds/#untyped-import), however i would still like pyrefly to report an error when using an untyped library even if there's no known stubs package, so that i can then decide whether to create stubs myself, or simply use a different library.

```py
from requests import check_compatibility # error: untyped-import
from pymsteams import TeamsWebhookException # no error
```

pyright's [`reportMissingTypeStubs`](https://docs.basedpyright.com/v1.39.5/configuration/config-files/#reportMissingTypeStubs) rule reports an error regardless of whether it knows about the stubs package