Apply uninlined-format-args clippy lint

This lint should also be applied to the excersies,
but I am not certain how to run it for all non-crate individual files.

To re-run:

```
rustup run nightly cargo clippy --fix -- -A clippy::all -W clippy::uninlined_format_args
```

src/exercise.rs

@@ -20,7 +20,7 @@ fn temp_file() -> String {
         .filter(|c| c.is_alphanumeric())
         .collect();
 
-    format!("./temp_{}_{}", process::id(), thread_id)
+    format!("./temp_{}_{thread_id}", process::id())
 }
 
 // The mode of the exercise.