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/ide-completion/src/completions/snippet.rs

@@ -141,7 +141,7 @@ fn add_custom_completions(
             };
             let body = snip.snippet();
             let mut builder = snippet(ctx, cap, trigger, &body);
-            builder.documentation(Documentation::new(format!("```rust\n{}\n```", body)));
+            builder.documentation(Documentation::new(format!("```rust\n{body}\n```")));
             for import in imports.into_iter() {
                 builder.add_import(import);
             }