examples: compare-tokens: use .first() instead of .get(0)

Clippy suggests that .first() is more readable than .get(0).

Author: piodul

examples/compare-tokens.rs

@@ -45,7 +45,7 @@ async fn main() -> Result<()> {
             .await?
             .rows
             .unwrap()
-            .get(0)
+            .first()
             .expect("token query no rows!")
             .columns[0]
             .as_ref()