Communication: Fix an issue with unread message count (#10245)

src/main/java/de/tum/cit/aet/artemis/communication/repository/conversation/ConversationRepository.java

@@ -52,7 +52,7 @@ public interface ConversationRepository extends ArtemisJpaRepository<Conversatio
             FROM Conversation conv
                 LEFT JOIN Channel channel ON conv.id = channel.id
                 LEFT JOIN ConversationParticipant cp ON conv.id = cp.conversation.id AND cp.user.id = :userId
-                LEFT JOIN Post p ON conv.id = p.conversation.id AND (p.creationDate > cp.lastRead OR (channel.isCourseWide = TRUE AND cp.lastRead IS NULL))
+                LEFT JOIN Post p ON conv.id = p.conversation.id AND p.author.id <> :userId AND (p.creationDate > cp.lastRead OR (channel.isCourseWide = TRUE AND cp.lastRead IS NULL))
             WHERE conv.id IN :conversationIds
                 AND (channel.isCourseWide = TRUE OR (conv.id = cp.conversation.id AND cp.user.id = :userId))
             GROUP BY conv.id, cp.id, cp.isModerator, cp.isFavorite, cp.isHidden, cp.lastRead
@@ -84,6 +84,7 @@ SELECT COUNT(p.id) > 0
                 LEFT JOIN ConversationParticipant cp ON c.id = cp.conversation.id AND cp.user.id = :userId
                 LEFT JOIN Channel ch ON c.id = ch.id
             WHERE c.course.id = :courseId
+            AND p.author.id <> :userId
             AND (
                 p.creationDate > cp.lastRead OR
                 (ch.isCourseWide = TRUE AND cp.id IS NULL)