MM-34609 Mark-as-unread on a post in a thread should cause auto-follow (#17343)

Co-authored-by: Mattermod <mattermod@users.noreply.github.com>

app/user.go

@@ -2424,7 +2424,7 @@ func (a *App) UpdateThreadsReadForUser(userID, teamID string) *model.AppError {
 }
 
 func (a *App) UpdateThreadFollowForUser(userID, teamID, threadID string, state bool) *model.AppError {
-	err := a.Srv().Store.Thread().MaintainMembership(userID, threadID, state, false, true, false)
+	_, err := a.Srv().Store.Thread().MaintainMembership(userID, threadID, state, false, true, false)
 	if err != nil {
 		return model.NewAppError("UpdateThreadFollowForUser", "app.user.update_thread_follow_for_user.app_error", nil, err.Error(), http.StatusInternalServerError)
 	}