fix mispositioned span
This fixes#47377
The output now looks like this
```
error[E0369]: binary operation `+` cannot be applied to type `&str`
--> h.rs:3:11
|
3 | let _a = b + ", World!";
| ^^^^^^^^^^^^^^ `+` can't be used to concatenate two `&str` strings
help: `to_owned()` can be used to create an owned `String` from a string reference. String concatenation appends the string on the right to the string on the left and may require reallocation. This requires ownership of the string on the left
|
3 | let _a = b.to_owned() + ", World!";
| ^^^^^^^^^
error: aborting due to previous error
```
For the case when emojis are involved, it gives the new output for proper indentation.
But for an indentation as follows,
```
fn main() {
let b = "hello";
let _a = b + ", World!";
}
```
it still mispositions the span
```
3 | println!("🦀🦀🦀🦀🦀"); let _a = b + ", World!";
| ^^^^^^^^^^^^^^ `+` can't be used to concatenate two `&str` strings
|
3 | println!("🦀🦀🦀🦀🦀"); let _a = b.to_owned() + ", World!";
| ^^^^^^^
error: aborting due to previous erro
```
cc @estebank @est31
bd8aa02ff4