Prevent crash if telegram message failed and did not generate an ID (#137989)

Fix #137901 - Regression introduced in 6fdccda225

homeassistant/components/telegram_bot/__init__.py

@@ -756,6 +756,7 @@ class TelegramNotificationService:
                 message_thread_id=params[ATTR_MESSAGE_THREAD_ID],
                 context=context,
             )
+            if msg is not None:
                 msg_ids[chat_id] = msg.id
         return msg_ids