fix test

Sometimes the path is unixified, sometimes not, so better don't
care about the slash in this case.

Author: weltling

ext/phar/tests/bug69441.phpt

@@ -14,7 +14,7 @@ $r = new Phar($fname, 0);
 
 ==DONE==
 --EXPECTF--
-exception 'UnexpectedValueException' with message 'phar error: corrupted central directory entry, no magic signature in zip-based phar "%s%ebug69441.phar"' in %s%ebug69441.php:%d
+exception 'UnexpectedValueException' with message 'phar error: corrupted central directory entry, no magic signature in zip-based phar "%sbug69441.phar"' in %sbug69441.php:%d
 Stack trace:
 #0 %s%ebug69441.php(%d): Phar->__construct('%s', 0)
 #1 {main}