fix an issue that it can't be operated after the login dialog closing

src/slic3r/GUI/WebSMUserLoginDialog.cpp

@@ -176,7 +176,7 @@ void SMUserLogin::OnNavigationRequest(wxWebViewEvent &evt)
         info->set_user_login(true);
         info->set_user_token(token);
 
-        this->Hide();
+        this->EndModal(wxID_OK);
 
         wxGetApp().CallAfter([info, this]() {
             std::string url  = m_userInfoUrl.ToStdString();