private void PbUpdateTester_Click(object sender, RoutedEventArgs e)
        {
            if (testerDataGrid.SelectedItem == null)
            {
                return;
            }
            var selectedPerson = (testerDataGrid.SelectedItem) as Tester;
            UpdateTesterWindow updateTesterWindow = new UpdateTesterWindow(selectedPerson);

            updateTesterWindow.ShowDialog();
        }
        private void TesterDataGrid_MouseDoubleClick(object sender, MouseButtonEventArgs e)
        {
            if (testerDataGrid.SelectedItem == null)
            {
                return;
            }
            var selectedPerson = (testerDataGrid.SelectedItem) as Tester;

            UpdateTesterWindow updateTesterWindow = new UpdateTesterWindow(selectedPerson);

            updateTesterWindow.ShowDialog();
        }