add missing lng-string (Fixes: 4120)

interface/web/help/lib/lang/ar_support_message.lng

interface/web/help/lib/lang/bg_support_message.lng

interface/web/help/lib/lang/br_support_message.lng

interface/web/help/lib/lang/ca_support_message.lng

interface/web/help/lib/lang/cz_support_message.lng

interface/web/help/lib/lang/de_support_message.lng

interface/web/help/lib/lang/dk_support_message.lng

interface/web/help/lib/lang/el_support_message.lng

interface/web/help/lib/lang/en_support_message.lng

interface/web/help/lib/lang/es_support_message.lng

interface/web/help/lib/lang/fi_support_message.lng

interface/web/help/lib/lang/fr_support_message.lng

interface/web/help/lib/lang/hr_support_message.lng

interface/web/help/lib/lang/hu_support_message.lng

interface/web/help/lib/lang/id_support_message.lng

interface/web/help/lib/lang/it_support_message.lng

interface/web/help/lib/lang/ja_support_message.lng

interface/web/help/lib/lang/nl_support_message.lng

interface/web/help/lib/lang/pl_support_message.lng

interface/web/help/lib/lang/pt_support_message.lng