do not normalize `use foo::{self}` to `use foo`
It changes behaviour and can cause collisions. E.g. for the following snippet
```rs
mod foo {
pub mod bar {}
pub const bar: i32 = 8;
}
// transforming the below to `use foo::bar;` causes the error:
//
// the name `bar` is defined multiple times
use foo::bar::{self};
const bar: u32 = 99;
fn main() {
let local_bar = bar;
}
```
we still normalize
```rs
use foo::bar;
use foo::bar::{self};
```
to `use foo::bar;` because this cannot cause collisions.
See: https://github.com/rust-lang/rust-analyzer/pull/17140#issuecomment-2079189725