fix: Update unread_messages count in WhatsApp inboxes (#6154)

* fix: Update unread_count from backend instead of computing on the frontend

* Fix spec

* Remove status indicator on private notifications

* CodeClimate fix

* CodeClimate

app/javascript/dashboard/store/modules/conversations/index.js

@@ -108,6 +108,8 @@ export const mutations = {
     } else {
       chat.messages.push(message);
       chat.timestamp = message.created_at;
+      const { conversation: { unread_count: unreadCount = 0 } = {} } = message;
+      chat.unread_count = unreadCount;
       if (selectedChatId === conversationId) {
         window.bus.$emit(BUS_EVENTS.SCROLL_TO_MESSAGE);
       }