update config folder link

Author: Arhell

config/bootstrap.php

@@ -102,7 +102,7 @@
 
 /*
  * Set the default server timezone. Using UTC makes time calculations / conversions easier.
- * Check http://php.net/manual/en/timezones.php for list of valid timezone strings.
+ * Check https://php.net/manual/en/timezones.php for list of valid timezone strings.
  */
 date_default_timezone_set(Configure::read('App.defaultTimezone'));