[4.1] Update Sites rebuild (#37617)

administrator/language/en-GB/com_installer.ini

@@ -170,7 +170,7 @@ COM_INSTALLER_MSG_UPDATESITES_DELETE_ERROR="An error has occurred while trying t
 COM_INSTALLER_MSG_UPDATESITES_N_DELETE_UPDATESITES_DELETED="%s update sites have been deleted."
 COM_INSTALLER_MSG_UPDATESITES_N_DELETE_UPDATESITES_DELETED_1="Update site has been deleted."
 COM_INSTALLER_MSG_UPDATESITES_REBUILD_EXTENSION_PLUGIN_NOT_ENABLED="The <a href=\"%s\">Joomla Extension Plugin</a> is disabled. This plugin must be enabled to rebuild the update sites."
-COM_INSTALLER_MSG_UPDATESITES_REBUILD_MESSAGE="Update sites have been rebuilt. No extension with an update site has been discovered."
+COM_INSTALLER_MSG_UPDATESITES_REBUILD_MESSAGE="Update sites have been rebuilt. No additional extension with an update site has been discovered."
 COM_INSTALLER_MSG_UPDATESITES_REBUILD_NOT_PERMITTED="Rebuilding update sites is not permitted."
 COM_INSTALLER_MSG_UPDATESITES_REBUILD_SUCCESS="Update sites have been rebuilt from manifest files."
 COM_INSTALLER_MSG_UPDATESITES_REBUILD_WARNING="Update sites have been rebuilt. No extension with updates sites discovered."