fix(issue): might have unwanted results

unwanted join with issues representing form answers

Signed-off-by: Thierry Bugier <tbugier@teclib.com>

hook.php

@@ -82,8 +82,10 @@ function plugin_formcreator_addDefaultJoin($itemtype, $ref_table, &$already_link
    $join = "";
    switch ($itemtype) {
       case PluginFormcreatorIssue::class:
+         // Get default joins for tickets
          $join = Search::addDefaultJoin("Ticket", "glpi_tickets", $already_link_tables);
-         $join = str_replace('`glpi_tickets`.`id`', '`glpi_plugin_formcreator_issues`.`original_id`', $join);
+         // but we want to join in issues
+         $join = str_replace('`glpi_tickets`.`id`', '`glpi_plugin_formcreator_issues`.`sub_itemtype` = "Ticket" AND `glpi_plugin_formcreator_issues`.`original_id`', $join);
          $join = str_replace('`glpi_tickets`', '`glpi_plugin_formcreator_issues`', $join);
          $join = str_replace('`users_id_recipient`', '`requester_id`', $join);
    }