fix dir separator in tests

Author: weltling

ext/date/tests/bug68942.phpt

@@ -6,4 +6,4 @@ $data = unserialize('a:2:{i:0;O:12:"DateTimeZone":2:{s:13:"timezone_type";a:2:{i
 var_dump($data);
 ?>
 --EXPECTF--
-Fatal error: DateTimeZone::__wakeup(): Timezone initialization failed in %s/bug68942.php on line %d
+Fatal error: DateTimeZone::__wakeup(): Timezone initialization failed in %s%ebug68942.php on line %d

ext/date/tests/bug68942_2.phpt

@@ -6,4 +6,4 @@ $data = unserialize('a:2:{i:0;O:8:"DateTime":3:{s:4:"date";s:26:"2000-01-01 00:0
 var_dump($data);
 ?>
 --EXPECTF--
-Fatal error: Invalid serialization data for DateTime object in %s/bug68942_2.php on line %d
+Fatal error: Invalid serialization data for DateTime object in %s%ebug68942_2.php on line %d