Fix true / false sprintf error

romanToInt.php

@@ -134,7 +134,7 @@ class Solution {
         }
 
         echo sprintf(
-            'Succeeded: The value of \'%d\' matched the expected value of \'%s\'' . PHP_EOL,
+            'Succeeded: The value of \'%s\' matched the expected value of \'%s\'' . PHP_EOL,
             $val ? 'True' : 'False',
             $str
         );