proc macro errors are attached to the wrong location in diagnostics.

[jhgg]

this is a regression of #12657 which was fixed by #12691

Here are some ways to reproduce it, each which seem to map the error span to weird locations:

use serde::Deserialize;

fn main() {}

#[derive(Deserialize)]
#[serde(rename_all = "wrong")]
struct Foo {}

And from the original issue report:

#[tokio::main(heck)]
async fn main() {}

fn world() {
    println!("hello");
    println!("hello");
    println!("hello");
    println!("hello");
    println!("hello");
    println!("hello");
    println!("hello");
    println!("hello");
    println!("hello");
}

rust-analyzer version: 0.4.1283-standalone
rustc version: 1.65.0 (897e37553 2022-11-02)

[Veykril]

We should probably try to make a test for this proc-macro behavior at least 😬 (curious to see what regressed this 🤔)