(🐞) 'warn-unreachable' doesn't reactivate after it is suppressed with a `<nothing>` statement

```py
from typing import NoReturn

def foo() -> NoReturn:
 raise Exception

def bar() -> NoReturn:
 foo()
 foo()
 print("hi") # no warning
```

The first call to `foo` is suppress the `unreachable` intentionally, (same with the second). But the `print("hi)` should definitely show an unreachable error.