docs: @Override
      public boolean logout(HttpServletRequest request, HttpServletResponse response, String userName) {
          boolean bSetSubject = false;
          if (tc.isDebugEnabled()) {
              Tr.debug(tc, "logout() userName:" + userName);
          }
  
          // Search all service and
          // 1) setSubject if subject match
          // 2) remove the cookie and its cached subject
          synchronized (this.socialLoginConfigRef) {
              Iterator<SocialLoginConfig> services = this.socialLoginConfigRef.getServices();
              SocialLoginConfig socialLoginConfig = null;
              while (services.hasNext()) {
                  socialLoginConfig = services.next();
                  // TODO remove all the cookies of the subject
              }
          }
          return bSetSubject;
      }