Fix failing test

Author: cmb69

ext/gd/tests/bug77479.phpt

@@ -15,7 +15,7 @@ imagewbmp($im, __DIR__ . '/77479.wbmp');
 ?>
 ===DONE===
 --EXPECTF--
-Warning: imagewbmp(): gd warning: product of memory allocation multiplication would exceed INT_MAX, failing operation gracefully
+Warning: imagewbmp():%S product of memory allocation multiplication would exceed INT_MAX, failing operation gracefully
  in %s on line %d
 
 Warning: imagewbmp(): Could not create WBMP in %s on line %d