move utils to classes folder

dta/locallib.php

@@ -18,9 +18,9 @@ defined('MOODLE_INTERNAL') || die();
 
 // Import various entity and application logic files.
 require_once($CFG->dirroot . '/mod/assign/submission/dta/models/DtaResult.php');
-require_once($CFG->dirroot . '/mod/assign/submission/dta/utils/database.php');
-require_once($CFG->dirroot . '/mod/assign/submission/dta/utils/backend.php');
-require_once($CFG->dirroot . '/mod/assign/submission/dta/utils/view.php');
+require_once($CFG->dirroot . '/mod/assign/submission/dta/classes/database.php');
+require_once($CFG->dirroot . '/mod/assign/submission/dta/classes/backend.php');
+require_once($CFG->dirroot . '/mod/assign/submission/dta/classes/view.php');
 
 /**
  * library class for DTA submission plugin extending assign submission plugin base class