doc: move "Prints: ..." under the code

PR-URL: https://github.com/nodejs/node/pull/27035
Reviewed-By: Vse Mozhet Byt <vsemozhetbyt@gmail.com>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>
Reviewed-By: Ruben Bridgewater <ruben@bridgewater.de>

doc/api/buffer.md

@@ -281,13 +281,13 @@ function:
 ```js
 const buf = Buffer.from([1, 2, 3]);
 
+for (const b of buf) {
+  console.log(b);
+}
 // Prints:
 //   1
 //   2
 //   3
-for (const b of buf) {
-  console.log(b);
-}
 ```
 
 Additionally, the [`buf.values()`], [`buf.keys()`], and