Inline all format arguments where possible

This makes code more readale and concise,
moving all format arguments like `format!("{}", foo)`
into the more compact `format!("{foo}")` form.

The change was automatically created with, so there are far less change
of an accidental typo.

```
cargo clippy --fix -- -A clippy::all -W clippy::uninlined_format_args
```

crates/hir-expand/src/fixup.rs

@@ -366,7 +366,7 @@ mod tests {
             fixups.append,
         );
 
-        let actual = format!("{}\n", tt);
+        let actual = format!("{tt}\n");
 
         expect.indent(false);
         expect.assert_eq(&actual);