MDL-78346 tool_langimport: Redirect after action to prevent resubmission

admin/tool/langimport/index.php

@@ -76,11 +76,12 @@ if (($mode == INSTALLATION_OF_SELECTED_LANG) and confirm_sesskey() and !empty($p
     if (is_array($pack) && count($pack) > 1) {
         // Installing multiple languages can take a while - perform it asynchronously in the background.
         $controller->schedule_languagepacks_installation($pack);
-
+        redirect($PAGE->url);
     } else {
         // Single language pack to be installed synchronously. It should be reasonably quick and can be used for debugging, too.
         core_php_time_limit::raise();
         $controller->install_languagepacks($pack);
+        redirect($PAGE->url);
     }
 }
 
@@ -109,7 +110,7 @@ if ($mode == DELETION_OF_SELECTED_LANG and (!empty($uninstalllang) or !empty($co
         foreach ($uninstalllang as $ulang) {
             $controller->uninstall_language($ulang);
         }
-
+        redirect($PAGE->url);
     }
 }