`UP029` triggers if import redefines previous import

### Description

```python
from math import *  # noqa: F403
from builtins import pow

pow(1, 1, 1)
```

https://play.ruff.rs/1f69e684-9b27-4626-ac06-4358cb6f9679

```python
from math import pow
from builtins import pow

pow(1, 1, 1)
```

https://play.ruff.rs/d86b74ac-4412-4ca6-a8ec-902a31dce30f

`from builtins import pow` should not trigger `UP029`, since the import is not a no-op in either case.