minor #11510 reformat code example (OskarStark)

This PR was submitted for the master branch but it was merged into the 3.4 branch instead (closes #11510).

Discussion
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reformat code example

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Commits
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b1d8732 reformat code example

Author: javiereguiluz

components/console/helpers/formatterhelper.rst

@@ -108,6 +108,7 @@ If you don't want to use suffix at all, just pass an empty string::
 
     $truncatedMessage = $formatter->truncate($message, 7, '!!'); // result: This is!!
     $truncatedMessage = $formatter->truncate($message, 7, '');   // result: This is
+
     $truncatedMessage = $formatter->truncate('test', 10);
-    /* result: test
-       because length of the "test..." string is shorter than 10 */
+    // result: test
+    // because length of the "test..." string is shorter than 10