URL Redirect and Bulk Actions in wp_list_table

Understand hierarchy, You don’t need to redirect as form are posting values on same page.

function process_bulk_action() {

    // Some security check code here

    // Get the bulk action
    $action = $this->current_action();

    if ($action == 'bulk_trash') {

        // Code for the "delete process" 
       $delete_ids = esc_sql($_POST['bulk-delete']);

       //loop over the array of record ids
       foreach($delete_ids as $id) {
            self::delete_item($id);
       }

       // show admin notice
       echo '<div class="notice notice-success is-dismissible"><p>Bulk Deleted..</p></div>';
   }

}

another method is prepare_items

public function prepare_items() {
      // first check for action
      $this->process_bulk_action();

      // then code to render your view.

}